Co-reporter:Xin Song, Rui Wang, Weifeng Zhao, Shudong Sun, Changsheng Zhao
Journal of Colloid and Interface Science 2017 Volume 485() pp:39-50
Publication Date(Web):1 January 2017
DOI:10.1016/j.jcis.2016.09.025
The removal of toxins is important due to the damage to aquatic environment. In this work, a facile and green approach based on mussel-inspired coatings was used to fabricate amino-coated particles via the reaction between amine and catechol, using hexanediamine as the representative amine. The particles were characterized by Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), thermo gravimetric analysis (TGA), and scanning electron microscopy (SEM). The particles showed selective adsorption capability to Congo red (CR) and the adsorption process fitted the pseudo-second-order model, the intraparticle diffusion model, the Langmuir isotherm, the Freundlich isotherm and the Sips isotherm well. Furthermore, this approach was verified to have applicability to various amines such as diethylenetriamine (DETA), triethylenetetramine (TETA) and tetraethylenepentamine (TEPA), and the amino-coated particles exhibited diverse adsorption capacities to CR, Cu2+ and bilirubin. Considering that the approach is easy to operate and the whole preparation process is in an aqueous solution, it is believed that the facile, green and economical approach has great potential to prepare particles for wastewater treatment.
Co-reporter:Xiang Zhang, Jukai Zhou, Ran Wei, Weifeng Zhao, Shudong Sun, Changsheng Zhao
Journal of Membrane Science 2017 Volume 535(Volume 535) pp:
Publication Date(Web):1 August 2017
DOI:10.1016/j.memsci.2017.04.044
•Poly(ionic liquid)s modified membranes were prepared by a facile one-pot method.•The fluxes of the membranes show obvious ion strength responsive behavior.•The membranes show ion-exchange property when contact with different salt solutions.•The pure water fluxes of the membranes show ion species responsive behavior.A series of poly(ionic liquid)s (PILs) modified polyethersulfone membranes were fabricated via an in-situ cross-linking copolymerization method. Due to the positive charge and ion-exchange properties of the PILs, the membranes showed anion species and strength responsive behaviors. The morphologies and chemical compositions of the membranes were characterized by scanning electron microscope and X-ray photoelectron spectroscopy. The anion species and strength responsive properties were investigated by measuring the fluxes of the membranes with various anion species and concentrations of salt solutions. The anion strength response of the membranes was positive, and the responsive coefficient of the membranes (the ratio of the salt water flux to pure water flux) could reach 26 times when responded to the stimulus of NaCl aqueous solution; the cation species and concentrations had barely influence on the responsive behavior. Meanwhile, the membranes were responded to both anion species (including PF6−, BF4− and SCN-) and their strength: the pure water fluxes and the morphologies of the modified membranes changed associated with different types of anions, and the membranes after ion-exchanging also showed obvious anion strength responsive behaviors to the corresponding salt solutions. The facile design of anion-responsive membranes via in-situ cross-linking polymerization opens up a new route to fabricate “intelligent” membranes for ion-recognizable chemical/biomedical separations and purifications.
Co-reporter:Min He, Huiyi Jiang, Rui Wang, Yi Xie, Changsheng Zhao
Journal of Colloid and Interface Science 2017 Volume 490(Volume 490) pp:
Publication Date(Web):15 March 2017
DOI:10.1016/j.jcis.2016.11.062
To develop a biologically mimetic guided tissue regeneration (GTR) membrane with localized sustained drug release function to prevent infection, coaxial electrospinning technique was conducted to fabricate metronidazole (MNA)-loaded poly (ε-caprolactone) (PCL)/zein core/shell nanofibers. The nanofibers displayed a uniform bead-free round morphology as observed by scanning electron microscopy (SEM), and a core/shell structure as confirmed by transmission electron microscopy (TEM). X-ray diffraction (XRD) and differential scanning calorimetry (DSC) characterizations demonstrated that the MNA was well dispersed in the nanofibers matrix. Due to the encapsulation of the hydrophobic zein, the MNA was released in a controlled, sustained manner over 4 days, and the released MNA showed high antibacterial activity towards anaerobic bacteria. In addition, the encapsulation of natural zein resulted in enhanced cell adhesion and proliferation, and the loading of MNA did not show any cytotoxicity. Thus, these results demonstrated that the MNA-loaded core/shell nanofibers had the potential to be used as GTR membranes with antibacterial function for extensive biomedical applications.Download high-res image (129KB)Download full-size image
Co-reporter:Chuanxiong Nie, Ye Yang, Zihang Peng, Chong Cheng, Lang Ma, Changsheng Zhao
Journal of Membrane Science 2017 Volume 528(Volume 528) pp:
Publication Date(Web):15 April 2017
DOI:10.1016/j.memsci.2016.12.070
•Aramid nanofiber (ANF) act as hydrophilic but non-dissolvable nanofibrous modifier.•ANF can be incorporated into PES and PSf ultrafiltration membrane by bulk blending.•Modified composite membranes own improved wet-ability and highly enhanced porosity.•Membrane antifouling properties and hemo-compatibility are greatly improved by ANF.•ANF enabled composite membranes with higher toxins removal efficiency in hemodialysis.Improving the filtration and biological performances of polymeric membranes has become a major bottle-neck to forward the membrane based separation and purification technologies. Herein, for the first time, we report the usage of aramid nanofiber (ANF) to enhance the ultrafiltration and biological performances of polysulfone (PSf) and polyethersulfone (PES) membranes. ANF is a relatively hydrophilic additive with a water contact angle around 40°; however, different from many other hydrophilic or amphiphilic additives, ANF is completely stable and non-dissolvable in water, which makes it an ideal modifier for generating hydrophilic composite membranes. After the addition of ANF, the membranes exhibit more porous structures and enhanced surface hydrophilicity. The flux recovery ratio, protein adsorption and bacterial adhesion tests validate that the ANF modified membranes own improved antifouling properties. Notably, the ANF modified membranes also show improved blood compatibility in terms of limited protein adsorption, suppressed platelet adhesion and activation, inhibited coagulant factors and complementary factors activation. Furthermore, the addition of ANF enables more efficient adsorption of small molecular creatinine toxins during dialysis applications of the composite membranes. In general, this hydrophilic, low-cost, and nanofibrous ANF modifier will be of promising potential for the modification of ultrafiltration membranes and forward their applications in water purification and hemodialysis.Download high-res image (293KB)Download full-size image
Co-reporter:Chuanxiong Nie, Ye Yang, Chong Cheng, Lang Ma, ... Changsheng Zhao
Acta Biomaterialia 2017 Volume 51(Volume 51) pp:
Publication Date(Web):15 March 2017
DOI:10.1016/j.actbio.2017.01.027
The design of self-sterilizing surfaces with favorable biocompatibility is acknowledged as an effective approach to deal with the bacterial infections of biomedical devices. In this study, we report an intriguing protocol for the large-scale fabrication of self-sterilizing and biocompatible surface film coatings by using polymer shielded silver nanoparticle loaded oxidized carbon nanotube (AgNPs@oCNT) nano-dispersions. To achieve the antibacterial coatings, the bioinspired positively charged and negatively charged AgNPs@oCNTs were alternately deposited onto substrates by spray-coating assisted layer-by-layer assembly. Then the bacterial inhibitory zones, optical density value monitoring, bacterial killing efficiency and adhesion were investigated; and all the results revealed that the AgNPs@oCNTs thin film coatings exhibited robust and long-term antibacterial activity against both Gram negative and Gram positive bacteria. Moreover, due to the shielding effects of polymer layers, the coatings showed extraordinary blood compatibility and limited toxicity against human umbilical vein endothelial cells. It is believed that the proposed large-scale fabrication of bactericidal, blood and cell compatible AgNPs@oCNT based thin film coatings will have great potential to forward novel operational pathogenic inhibition strategies to avoid undesired bacterial contaminations of biomedical implants or biological devices.Statement of SignificanceBacterial infection of medical devices has been considered to be a world-wide clinical threat towards patients’ health. In this study, a bioinspired and biocompatible antibacterial coating was prepared via the spray-assisted layer-by-layer (LbL) assembly. The silver nanopartilces loaded oxidized carbon nanotube (AgNPs@oCNT), which were coated by functional polymers (chitosan and synthetic heparin mimicking polymers), were prepared via mussel inspired chemistry; and the spray-assisted assembly process allowed the fast construction on devices. Owing to the antibacterial efficiency of the loaded AgNPs, the coating showed robust bacterial killing activity and resistance towards bacterial adhesion. Moreover, since that the AgNPs were shielded by the polymers, the coating exhibited no clear toxicity at blood or cellular level. Benefiting from the universal and large-scale fabrication advancements of the spray assisted LbL coating; it is believed that the proposed strategy can be applied in designing many other kinds of self-sterilizing biomedical implants and devices.Download high-res image (212KB)Download full-size image
Co-reporter:Rui Wang, Xin Song, Tao Xiang, Qiang Liu, Baihai Su, Weifeng Zhao, Changsheng Zhao
Carbohydrate Polymers 2017 Volume 168(Volume 168) pp:
Publication Date(Web):15 July 2017
DOI:10.1016/j.carbpol.2017.03.092
•Chitosan/polyurethane (CS/PU) coating with Ag nanoparticles (AgNPs) was fabricated.•The coating endowed membranes with antifouling and dual-antibacterial properties.•The coating exhibited lasting antifouling property after exhausting AgNPs.•The coating could be regenerated to reload AgNPs for long-term use.A straightforward mussel-inspired approach was proposed to construct chitosan-polyurethane coatings and load Ag nanoparticles (AgNPs) to endow polyethersulfone (PES) membranes with dual-antibacterial and antifouling properties. The macromolecule O-carboxymethyl chitosan (CMC) was directly reacted with catechol in the absence of carbodiimide chemistry to form the coating and load AgNPs via in situ reduction; while lysine (Lys) was used as a representative small molecule for comparison. Then, PEG-based polyurethane (PU) was used for constructing Lys-Ag-PU and CMC-Ag-PU composite coatings, which substantially improved the protein antifouling property of the membranes. Furthermore, the CMC-Ag-PU coating exhibited superior broad-spectrum antibacterial property towards E. coli and S. aureus than Lys-Ag-PU coating. Meanwhile, the CMC-Ag-PU coating showed sustained antifouling property against bacteria and could reload AgNPs to be regenerated as antibacterial and antifouling coating. This approach is believed to have potential to fabricate reusable antifouling and antibacterial coatings on materials surfaces for aquatic industries.
Co-reporter:Min He, Qian Wang, Zhenqiang Shi, Yi Xie, Weifeng Zhao, Changsheng Zhao
Colloids and Surfaces B: Biointerfaces 2017 Volume 158(Volume 158) pp:
Publication Date(Web):1 October 2017
DOI:10.1016/j.colsurfb.2017.07.035
•An drug conjugated hydrogel coating was designed.•The drug release was inflammation-responsive.•The drug released from the hydrogel coating retained bioactivity.•The coating showed no cytotoxicity.Heterotopic ossification(HO) is a potential severe complication after many biomaterial implanting surgeries, and the inflammation environment caused by the implanting-associated infections is considered as the main nosogenesis. Herein, an inflammation-responsive drug release system was designed by chemically conjugating indometacin (via ester group) onto hydrogel coating to realize local self-regulated drug release to prevent HO. In our strategy, poly(3-mercaptopropyl)trimethoxysilane-co-acrylic acrylate and polyvinyl alcohol (providing anchoring sites for drug molecules) were firstly synthesized and functionalized with ene-groups, then a hydrogel layer was formed and covalently attached onto thiol-modified substrate via thiol-ene click chemistry, followed by grafting indometacin. A porous structure of the attached hydrogel layer was observed by scanning electron microscopy, and the presence of drug molecules in the hydrogel layer was confirmed by X-ray photoelectron spectroscopy and UV–vis absorption spectra. The drug release could be triggered under the mimicking inflammation environment, and the release rate was responsive to the inflammation degree. In addition, after attaching the hydrogel coating, the substrate showed low cytotoxicity, and high promotion for cell adhesion and proliferation. The excellent hemocompatibility of the hydrogel coating was also demonstrated by prolonged clotting time and suppressed platelet adhesion. This work suggests that the inflammation-responsive indometacin conjugated hydrogel coating has great potential to be used for prophylaxis HO.Download high-res image (195KB)Download full-size image
Co-reporter:Shengqiu Chen, Xiang Zhang, Hao Huang, Man Zhang, Chuanxiong Nie, Ting Lu, Weifeng Zhao, Changsheng Zhao
Journal of Environmental Chemical Engineering 2017 Volume 5, Issue 2(Issue 2) pp:
Publication Date(Web):1 April 2017
DOI:10.1016/j.jece.2017.03.013
•A macroscopic microgels-contained core@shell beads adsorbent was prepared via a phase inversion technique.•The beads adsorbent performed well in the adsorption and desorption of dyes.•The beads adsorbent was ease of handling and reusability.In this study, a novel core@shell bead adsorbent was fabricated by using poly (acrylic acid) (PAA) microgels and polyethersulfone (PES) via a facile and versatile strategy for dye uptake from wastewater. PAA microgels were synthesized by distillation precipitation polymerization, followed by enwrapping with PES films to form core@shell beads by a phase inversion technique. The scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) mapping confirmed that the bead had a core@shell structure with PAA microgels in the core and PES on the shell. Batch adsorption experiments indicated that the contact time, initial dye concentration, adsorbent dosage, pH and ionic strength greatly affected the adsorption process. The beads could adsorb methylene blue as high as 84.82 mg/g while the adsorption capacities of methyl violet, rhodamine B, amaranth red and methyl orange were 43.37, 14.60, 2.93 and 2.29 mg/g, respectively. Simultaneously, the beads were recyclable for the removal of dye and the adsorption process fitted well with the non-linear Freundlich isotherm. All the results indicated that the prepared beads were promising in dye treatment.Download high-res image (200KB)Download full-size image
Co-reporter:Jie Deng, Xinyue Liu, Lang Ma, Chong Cheng, Shudong Sun and Changsheng Zhao
Journal of Materials Chemistry A 2016 vol. 4(Issue 4) pp:694-703
Publication Date(Web):17 Dec 2015
DOI:10.1039/C5TB02072G
The development of biointerfaces with switchable properties is of growing interest for fabricating advanced biomaterials since the adjustment of surface properties can be made on demand. Herein, we report a highly versatile approach for the preparation of a switchable biointerface through a dynamic covalent bond (DCB). The switchability can be achieved via the reversible attaching/detaching of aldehyde end-functionalized biomacromolecules onto/from an acylhydrazide anchored substrate surface. By applying the DCB protocol, three types of well-designed aldehyde end-functionalized biomacromolecules including aldehyde-poly(styrenesulfonate)-co-poly(ethylene glycol)methyl ether methacrylate (Ald-PSP, blood compatible), aldehyde-poly([2-(meth acryloyloxy)ethyl]trimethylammonium chloride) (Ald-PMT, antibacterial), and aldehyde-poly([2-(meth acryloyloxy)ethyl]trimethylammonium chloride-co-poly(ethylene glycol)methyl ether methacrylate) (Ald-PMP, combined antifouling and antibacterial) could be reversibly and alterably immobilized on the substrate surface by switching the pH conditions. As a result, we succeeded in altering the biointerface performances; excellent blood compatibility, antibacterial ability, or combined antifouling and antibacterial capabilities could be alterably achieved on the biointerface, which made the obtained material interfaces more adaptable and capable of satisfying different biofunctional requirements. Moreover, many other properties with specific biofunctions of interests can also be achieved via designing specific aldehyde-terminated molecules.
Co-reporter:Lang Ma, Chong Cheng, Chuanxiong Nie, Chao He, Jie Deng, Lingren Wang, Yi Xia and Changsheng Zhao
Journal of Materials Chemistry A 2016 vol. 4(Issue 19) pp:3203-3215
Publication Date(Web):22 Mar 2016
DOI:10.1039/C6TB00636A
In this work, we synthesized novel sodium alginate sulfates (SASs) with different sulfation degrees, which had similar chemical structure and bioactivity as those of heparin. Blood clotting time tests indicated that the heparin-mimetic SASs exhibited excellent and sulfation-degree-dependent anticoagulant activity. Beyond applications as anticoagulant reagents, the heparin-mimetics also showed potential applications for surface modification of blood-contacting devices. To achieve the goal of surface modification, we synthesized the mussel inspired adhesive macromolecules, dopamine grafted SASs (DA-g-SASs), which were capable of coating the surface of polymeric substrates in a basic buffer solution in a substrate-independent manner. The DA-g-SASs exhibited substrate-independent adhesive affinity to a variety of solid surfaces due to the formation of irreversible covalent bonds. By using polyethersulfone (PES) as a model blood contacting substrate, the surface properties of DA-g-SASs coated substrates were fully explored. ATR-FTIR and XPS spectra demonstrated the successful formation of the heparin-mimetic coatings. Endothelial cell staining and morphological observations revealed that the heparin-mimetic coatings could significantly promote cell adhesion and proliferation. In addition, systematic in vitro studies of blood clotting, protein adsorption, platelet adhesion, and blood-related complement activation demonstrated that the heparin-mimetic macromolecule coated substrates dramatically inhibited the thrombotic potential and inflammation induced by the material interface. Combining the above advantages, it is believed that the proposed integration of heparin-mimetic SASs and mussel inspired coating may open new operational principles for surface anticoagulant modification of various biological and clinical devices for blood purification, tissue implants, and other micro-nanoscale materials.
Co-reporter:Chuanxiong Nie, Chong Cheng, Zihang Peng, Lang Ma, Chao He, Yi Xia and Changsheng Zhao
Journal of Materials Chemistry A 2016 vol. 4(Issue 16) pp:2749-2756
Publication Date(Web):08 Mar 2016
DOI:10.1039/C6TB00470A
Silver nanoparticle (AgNP)-based nanohybrids have been proposed as efficient antimicrobial agents because of their robust bactericidal activity. However, the direct exposure of AgNPs poses a threat towards mammalian cells. In this article, we report a facile mussel-inspired approach to introduce functional biopolymer coatings to shield AgNP-loaded oxidized carbon nanotubes (AgNPs@oCNT), as well as to modify the interface properties. Two kinds of dopamine-grafted functional biopolymers, heparin and chitosan, were used to reduce the Ag+ ions pre-absorbed onto the oCNT surface and simultaneously form protective coating layers. Their effects on the bactericidal activity and mammal cell biocompatibility of the AgNPs@oCNT were compared. The TEM, FTIR, and XPS results clearly verified the loading of AgNPs and the coating of functional biopolymer on the oCNT surface. Studies of broth turbidity, bacterial growth kinetics, agar plate counts, and live/dead bacterial staining revealed that the biopolymer-coated nanohybrids exhibited robust bactericidal activity against both Gram negative and Gram positive bacteria, and were as effective as bare AgNPs@oCNT hybrids. The chitosan-coated samples were particularly effective because of the synergistic effects of chitosan and AgNPs. The shielding effects of the anchored functional biopolymers gave the AgNP-based nanohybrids good compatibility with endothelial cells, especially for the heparin-coated samples.
Co-reporter:Min He, Huiyi Jiang, Rui Wang, Yi Xie, Weifeng Zhao, Changsheng Zhao
Journal of Colloid and Interface Science 2016 Volume 484() pp:60-69
Publication Date(Web):15 December 2016
DOI:10.1016/j.jcis.2016.08.066
In this study, a robust and straightforward method to covalently attach multi-functional hydrogel thin layers onto substrates was provided. In our strategy, double bonds were firstly introduced onto substrates to provide anchoring points for hydrogel layers, and then hydrogel thin layers were prepared via surface cross-linking copolymerization of the immobilized double bonds with functional monomers. Sulfobetaine methacrylate (SBMA), sodium allysulfonate (SAS), and methyl acryloyloxygen ethyl trimethyl ammonium chloride (METAC) were selected as functional monomers to form hydrogel layers onto polyether sulfone (PES) membrane surfaces, respectively. The thickness of the formed hydrogel layers could be controlled, and the layers showed excellent long-term stability. The PSBMA hydrogel layer exhibited superior antifouling property demonstrated by undetectable protein adsorption and excellent bacteria resistant property; after attaching PSAS hydrogel layer, the membrane showed incoagulable surface property when contacting with blood confirmed by the activated partial thromboplastin time (APTT) value exceeding 600 s; while, the PMETAC hydrogel thin layer could effectively kill attached bacteria. The proposed method provides a new platform to directly modify material surfaces with desired properties, and thus has great potential to be widely used in designing materials for blood purification, drug delivery, wound dressing, and intelligent biosensors.
Co-reporter:Zihang Peng, Ye Yang, Jiyue Luo, Chuanxiong Nie, Lang Ma, Chong Cheng and Changsheng Zhao
Biomaterials Science 2016 vol. 4(Issue 9) pp:1392-1401
Publication Date(Web):02 Aug 2016
DOI:10.1039/C6BM00328A
Polymer based hemoperfusion has been developed as an effective therapy to remove the extra bilirubin from patients. However, the currently applied materials suffer from either low removal efficiency or poor blood compatibility. In this study, we report the development of a new class of nanofibrous absorbent that exhibited high bilirubin removal efficiency and good blood compatibility. The Kevlar nanofiber was prepared by dissolving micron-sized Kevlar fiber in proper solvent, and the beads were prepared by dropping Kevlar nanofiber solutions into ethanol. Owing to the nanofiborous structure of the Kevlar nanofiber, the beads displayed porous structures and large specific areas, which would facilitate the adsorption of toxins. In the adsorption test, it was noticed that the beads possessed an adsorption capacity higher than 40 mg g−1 towards bilirubin. In plasma mimetic solutions, the beads still showed high bilirubin removal efficiency. Furthermore, after incorporating with carbon nanotubes, the beads were found to have increased adsorption capacity for human degradation waste. Moreover, the beads showed excellent blood compatibility in terms of a low hemolysis ratio, prolonged clotting times, suppressed coagulant activation, limited platelet activation, and inhibited blood related inflammatory activation. Additionally, the beads showed good compatibility with endothelial cells. In general, the Kevlar nanofiber beads, which integrated with high adsorption capacity, good blood compatibility and low cytotoxicity, may have great potential for hemoperfusion and some other applications in biomedical fields.
Co-reporter:Chao He, Zhen-Qiang Shi, Chong Cheng, Chuan-Xiong Nie, Mi Zhou, Ling-Ren Wang and Chang-Sheng Zhao
RSC Advances 2016 vol. 6(Issue 76) pp:71893-71904
Publication Date(Web):22 Jul 2016
DOI:10.1039/C6RA14592B
Research on the design of heparin-analogue hydrogels is of tremendous importance and fuelled by diverse emerging biomedical applications, such as cancer inhibition, treatments of genetic diseases, growth factor carriers, and scaffolds for regeneration medicine, due to their specific biological and biocompatible properties. In this study, by taking inspiration from recent advancements of graphene nanomaterials and heparin-analogue polymers, we designed a kind of highly swellable, elastic, hemo- and cyto-compatible graphene oxide (GO) hybridized heparin-analogue hydrogels for potential drug and protein delivery. The fabricated GO/heparin-analogue hydrogels (GHHs) exhibited an inner-interpenetrated porous structure and robust mechanical properties compared to the GO absent heparin-analogue hydrogel (HH). Notably, the GHHs showed excellent results for in vitro biocompatibility, such as red blood cell compatibility, anti-platelet adhesion and activation, low inflammation potential, high endothelial cell compatibility. Furthermore, after adding GO, the hydrogels showed improved loading and persistent release abilities of doxorubicin hydrochloride (DOX); the GHHs also demonstrated their potential for efficient protein loading and long-term releasing. Due to the integration of elastic mechanical properties, hemo- and cyto-compatibility, as well as drug and protein delivery abilities, the GO hybridized heparin-analogue hydrogels open up a new potential protocol for implantable drug and protein delivery therapies, and bioactive scaffolds for tissue regeneration.
Co-reporter:Jie Deng;Lang Ma;Xinyue Liu;Chong Cheng;Chuanxiong Nie
Advanced Materials Interfaces 2016 Volume 3( Issue 4) pp:
Publication Date(Web):
DOI:10.1002/admi.201500473
Co-reporter:Chuanxiong Nie, Chong Cheng, Lang Ma, Jie Deng, and Changsheng Zhao
Langmuir 2016 Volume 32(Issue 23) pp:5955-5965
Publication Date(Web):May 17, 2016
DOI:10.1021/acs.langmuir.6b00708
Nanointerfacial decoration of silver nanoparticles (AgNPs) is an ideal protocol to improve the antibacterial efficiency of diverse nanomaterials, including carbon nanotube (CNT), graphene, and many other intensively studied nanoarchitectures, which provides a tremendous possibility for designing advanced antibacterial biomaterials and biomedical devices. However, the direct exposure of AgNPs will lead to potential mammalian cell apoptosis and death, which significantly limits their biological applications. In this study, we demonstrated a green and one-step approach to achieve robust antibacterial and highly biocompatible AgNP–CNT composites. AgNPs were produced via mussel-inspired “one-step” in situ reduction and coating process and were anchored onto the surface of a CNT. Simultaneously, protective polymer layers were formed to shield the AgNPs to improve their biocompatibility. Because of the bactericidal efficiency of AgNPs, the composites showed robust antibacterial efficiency in terms of both inhibition of bacterial cell growth and bacterial killing activity. Moreover, owing to the shielding effects of the polymer coatings, the nanocomposites exhibited much improved compatibility with human umbilical vein endothelial cells compared with bare AgNP–CNTs. Furthermore, the nanocomposites exhibited good stability in psychological solutions. With integrated excellent antibacterial activity, cell compatibility, and long-term stability, it is believed that the synthesized AgNP–CNT composites will be of promising potential in antibacterial applications. Meanwhile, the proposed strategies can also be applied to fabricate many other kinds of AgNP-based composites because of the versatile functionality of catecholic polymers.
Co-reporter:Yi Xia, Chong Cheng, Rui Wang, Chao He, Lang Ma, Changsheng Zhao
Colloids and Surfaces B: Biointerfaces 2016 Volume 139() pp:199-210
Publication Date(Web):1 March 2016
DOI:10.1016/j.colsurfb.2015.12.018
•The microgels were synthesized by cross-linking of antifouling segments PEGMA and MAA.•The membranes were prepared via the physical blending of microgels with membrane matrix.•The modified membranes showed improved water flux and antifouling property.•The modified membranes owned great resistance capability to the bioadhesion of various organisms.Effective and robust anti-bioadhesion ultrafiltration membranes were fabricated in this paper via physically blending of anti-bioadhesion microgels. The microgels were synthesized by one-step cross-linking of antifouling segment, poly(ethylene glycol) methacrylate (PEGMA), and electrostatic repulsion segment, methylacrylic acid (MAA). Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) results indicated that large amounts of PEGMA and MAA polymers had been enriched on the membranes surface. Scanning electron microscope (SEM) indicated that the spherical PEGMA-MAA (PM) microgels might form interpenetrating structure with the membrane matrixes, and substantially increased the pore size of the membranes. Water contact angle (WCA), pore size distributions and ultrafiltration tests suggested that the hydrophilicity, porosity, water flux, and antifouling property for the modified membranes were significantly enhanced. More importantly, systematic anti-adhesion investigations of plasma proteins, platelets, bacteria and vein endothelial cells confirmed that the modified membranes owned strong resistance capability to the bioadhesion of various organisms. The results revealed that highly robust and effective anti-bioadhesion ultrafiltration membranes could be prepared via the proposed blending of PM microgels with membrane matrix, thus this approach should be potential in various biomedical or industrial filtration fields where anti-bioadhesion properties were highly demanded.
Co-reporter:Chong Cheng, Ai He, Chuanxiong Nie, Yi Xia, Chao He, Lang Ma and Changsheng Zhao
Journal of Materials Chemistry A 2015 vol. 3(Issue 20) pp:4170-4180
Publication Date(Web):15 Apr 2015
DOI:10.1039/C5TB00136F
This study reports a highly efficient, convenient and universal protocol for the fabrication of robust antifouling and antibacterial polymeric membranes via one-pot cross-linked copolymerization of methyl acryloyloxygen ethyl trimethyl ammonium chloride (DMC) and poly(ethylene glycol) methyl ether methacrylate (PEGMA). The infrared testing and X-ray photoelectron spectroscopy gave obvious evidence that abundant DMC and PEGMA chains had enriched on the membrane surface. The surface and cross-sectional SEM images indicated that the addition of DMC and PEGMA had a little effect on the membrane roughness and inner structure. Meanwhile, the systematic investigations into the water contact angle, protein adsorption, ultrafiltration and bacterial inhibition indicated that the composite membranes showed improved hydrophilicity, decreased protein adsorption, increased water flux and antifouling property, as well as greatly enhanced antibacterial ability. Furthermore, it was found that the cross-linked copolymerization could further endow the composite membrane with multi-chemical properties, for instance the charged interface. As a model system, Ag nanoparticle-PDMC multilayers were coated onto the positively charged PES–DMC6 membranes via layer by layer assembly, and the successful surface coating confirmed their versatile ability and also provided a more effective and durable antibacterial coating to the composite membranes. All these results suggest that the robust antifouling and antibacterial composite membranes can be prepared via the proposed one-pot cross-linked copolymerization, and it is believed that this approach has great potential to be applied in various biomedical or industrial fields where antifouling and antibacterial properties are highly demanded.
Co-reporter:Chao He, Zhen-Qiang Shi, Lang Ma, Chong Cheng, Chuan-Xiong Nie, Mi Zhou and Chang-Sheng Zhao
Journal of Materials Chemistry A 2015 vol. 3(Issue 4) pp:592-602
Publication Date(Web):11 Nov 2014
DOI:10.1039/C4TB01806K
Studies on the design of heparin and heparin-mimicking polymer based hydrogels are of tremendous interest and are fuelled by diverse emerging biomedical applications, such as antithrombogenic materials, growth factor carriers, and scaffolds for tissue engineering and regeneration medicine. In this study, inspired by the recent developments of heparin-based hydrogels, graphene oxide (GO) based heparin-mimicking hydrogels with hemocompatibility and versatile properties were prepared via free radical copolymerization, and poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 2-hydroxyethyl methacrylate (HEMA) hydrogels were used as the control samples. The GO based heparin-mimicking polymeric hydrogels exhibited interconnected structures with thin pore walls and high porosity. Because of the increased ionization and electrostatic repulsion of sodium styrene sulfonate (SSNa) segments, the swelling ratios of the SSNa added hydrogels were dramatically increased; after incorporating flexible GO nanosheets, as the 3D skeleton of the hydrogels, the swelling ability was further increased. In addition, the GO based heparin-mimicking hydrogels showed superior red blood cell compatibility, anti-platelet adhesion ability and anticoagulant ability. Furthermore, drug release data indicated that the GO based heparin-mimicking hydrogels had high drug loading ability and prolonged drug releasing ability; the antibacterial tests showed coincident results with large inhibition zones and long effective periods. Due to the integration of blood compatibility, drug loading and releasing abilities, as well as an excellent ability for the removal of toxic molecules, the GO based heparin-mimicking hydrogels can be used for versatile biomedical applications.
Co-reporter:Lingren Wang, Baihai Su, Chong Cheng, Lang Ma, Shuangsi Li, Shengqiang Nie and Changsheng Zhao
Journal of Materials Chemistry A 2015 vol. 3(Issue 7) pp:1391-1404
Publication Date(Web):18 Dec 2014
DOI:10.1039/C4TB01865F
In this study, to approach the scalable fabrication of super-hemocompatible and antibacterial membranes, surface engineered 3D heparin-mimicking coatings were designed by layer by layer (LBL) assembly of water-soluble heparin-mimicking polymer (WHP) and quaternized chitosan (QC). The low cost and scalable WHP was synthesized by a combination of polycondensation and post-carboxylation method, and the antibacterial QC was prepared by a two-step quaternization reaction. Then, the as-prepared negatively charged WHP and positively charged QC were used to conduct the LBL assembly on the widely used poly(ether sulfone) (PES) membrane surface to prepare heparin-mimicking modified membrane. The results indicated that the assembled heparin-mimicking coating nanofilms exhibited 3D porous morphology. The systematic blood compatibility and antithrombotic evaluation revealed that the functionalized membrane owned prolonged clotting times and greatly suppressed platelet adhesion and activation; further contacting activation detection (TAT and PF-4) and complement activation (C3a and C5a) experiments indicated that the heparin-mimicking membranes had lower blood activation compared to the pristine membrane. The cell observations demonstrated that the surface assembled heparin-mimicking nanofilms showed superior performances in endothelial cells adhesion and growth than the pure PES membrane. The results of the antibacterial study indicated that the QC contained coating exhibited significant inhibition ability for both Escherichia coli and Staphlococcus aureus. In general, the LBL assembled heparin-mimicking coatings conferred the functionalized PES membranes with integrated blood compatibility, cytocompatibility and antibacterial property for multi-applications, which may forward the fabrication and application of heparin-mimicking biomedical devices.
Co-reporter:Yi Xia, Chong Cheng, Rui Wang, Chuanxiong Nie, Jie Deng and Changsheng Zhao
Journal of Materials Chemistry A 2015 vol. 3(Issue 48) pp:9295-9304
Publication Date(Web):09 Nov 2015
DOI:10.1039/C5TB01523E
A highly efficient, universal and convenient protocol is reported to fabricate antifouling, hemocompatible, and bactericidal membranes by physically blending antifouling nanogels and in situ silver nanoparticle immobilization. Firstly, nanogels are synthesized by one-step cross-linking co-polymerization of an antifouling monomer, poly(ethylene glycol) methacrylate (PEGMA), and an anchoring monomer, methylacrylic acid (MAA). Then, the nanogels are physically blended with a membrane matrix to generate nanogel embedded composite membranes. Finally, the in situ growth of silver nanoparticles in the composite membranes is successfully achieved by electrostatic adsorption of Ag+ ions and vitamin C reduction. The successful preparation of Ag-nanogel blended polymeric membranes has been confirmed by FTIR spectra and XPS patterns. The surface SEM images suggest that there are abundant Ag-nanogels embedded on the composite membrane surfaces. The cross-sectional SEM images give clear evidence that the Ag-nanogel immobilized composite membranes have well-maintained finger-like structure with increased porosity; meanwhile, the uniform distribution of the Ag-nanogels in the membrane matrix is confirmed by elemental EDX mapping. The systematic tests of water contact angle, static protein adsorption and ultrafiltration experiments indicate that the hydrophilicity, water flux, and antifouling properties of the composite membranes are substantially improved. More importantly, prolonged blood clotting time and suppressed platelet adhesion/activation indicate that the composite membranes have better blood compatibility and ultralow thrombotic potential. Bactericidal studies reveal that the modified membranes exhibit remarkable inhibition and killing capability toward both S. aureus and E. coli bacteria. The results reveal that robust antifouling, hemocompatible, and bactericidal composite membranes have been prepared via the proposed blending of nanogels and loading of Ag nanoparticles. This approach is believed to have great potential for fabricating various multifunctional membranes for industrial and clinical usage.
Co-reporter:Lang Ma, Chong Cheng, Chao He, Chuanxiong Nie, Jie Deng, Shudong Sun, and Changsheng Zhao
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 47) pp:26050
Publication Date(Web):November 10, 2015
DOI:10.1021/acsami.5b09634
In this work, we designed a robust and heparin-mimetic hydrogel thin film coating via combined layer-by-layer (LbL) self-assembly and mussel-inspired post-cross-linking. Dopamine-grafted heparin-like/-mimetic polymers (DA-g-HepLP) with abundant carboxylic and sulfonic groups were synthesized by the conjugation of adhesive molecule, DA, which exhibited substrate-independent adhesive affinity to various solid surfaces because of the formation of irreversible covalent bonds. The hydrogel thin film coated substrates were prepared by a three-step reaction: First, the substrates were coated with DA-g-HepLP to generate negatively charged surfaces. Then, multilayers were obtained via LbL coating of chitosan and the DA-g-HepLP. Finally, the noncovalent multilayers were oxidatively cross-linked by NaIO4. Surface ATR-FTIR and XPS spectra confirmed the successful fabrication of the hydrogel thin film coatings onto membrane substrates; SEM images revealed that the substrate-independent coatings owned 3D porous morphology. The soaking tests in highly alkaline, acid, and concentrated salt solutions indicated that the cross-linked hydrogel thin film coatings owned high chemical resistance. In comparison, the soaking tests in physiological solution indicated that the cross-linked hydrogel coatings owned excellent long-term stability. The live/dead cell staining and morphology observations of the adhered cells revealed that the heparin-mimetic hydrogel thin film coated substrates had low cell toxicity and high promotion ability for cell proliferation. Furthermore, systematic in vitro investigations of protein adsorption, platelet adhesion, blood clotting, and blood-related complement activation confirmed that the hydrogel film coated substrates showed excellent hemocompatibility. Both the results of inhibition zone and bactericidal activity indicated that the gentamycin sulfate loaded hydrogel thin films had significant inhibition capability toward both Escherichia coli and Staphylococcus aureus bacteria. Combined the above advantages, it is believed that the designed heparin-mimetic hydrogel thin films may show high potential for applications in various biological and clinical fields, such as long-term hemocompatible and drug-loading materials for implants.Keywords: hemocompatible and antimicrobial coating; heparin-mimetic hydrogel film; LbL self-assembly; mussel-inspired chemistry;
Co-reporter:Tao Xiang, Chong-Dan Luo, Rui Wang, Zhi-Yuan Han, Shu-Dong Sun, Chang-Sheng Zhao
Journal of Membrane Science 2015 Volume 476() pp:234-242
Publication Date(Web):15 February 2015
DOI:10.1016/j.memsci.2014.11.045
•PES/PSBMA membranes were prepared via in situ cross-linked polymerization.•There was no elution of PSBMA in the process of membrane fabrication and application.•The modified membranes showed obvious ionic-strength-sensitive property.•The modified membranes showed excellent antifouling property and blood compatibility.A new method to prepare ionic-strength-sensitive membrane with improved anti-fouling property and blood compatibility is developed via in situ cross-linked polymerization of sulfobetaine methacrylate (SBMA) in polyethersulfone (PES) solution and a liquid–liquid phase separation technique. The modified membrane is characterized by attenuated total reflectance-Fourier transform infrared spectra (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), 1H NMR measurements, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and water contact angle (WCA) measurement. The membrane with high PSBMA content shows obvious ionic-strength-sensitive property and ionic-strength reversibility, which are expressed by the fluxes of salt solutions. Meanwhile, with the increase of the PSBMA content in the membrane, the anti-fouling property and blood compatibility are considerably improved.
Co-reporter:Chao He, Chong Cheng, Hai-Feng Ji, Zhen-Qiang Shi, Lang Ma, Mi Zhou and Chang-Sheng Zhao
Polymer Chemistry 2015 vol. 6(Issue 45) pp:7893-7901
Publication Date(Web):22 Sep 2015
DOI:10.1039/C5PY01377A
In this study, we report the rapid synthesis of robust, highly elastic and bioactive heparin-mimetic hydrogels by combining free radical polymerization with doped graphene oxide (GO) as the micro-crosslinker. In the hydrogel system, GO is covalently connected or bonded to the heparin-mimetic polymer networks since the initiated macromolecular radicals can attach to the double bonds of GO. As a result, the GO doped heparin-mimetic hydrogels reveal highly interpenetrating networks with increased small pores, thinner pore walls, and a narrow pore size distribution compared to pristine heparin-mimetic hydrogels. Meanwhile, the GO doped heparin-mimetic hydrogels can also sustain cyclic compressions with extremely high strain due to the reinforced mechanical strength and elastic properties. Furthermore, all of the heparin-mimetic hydrogels show excellent endothelial cell compatibility, and doping with GO can further improve the cell viability and promote the generation of actin filaments and extracellular matrix. Moreover, the heparin-mimetic hydrogels also show a high drug loading ability and a persistent releasing ability, thus exhibiting sustained antitumor cell activity; doping with GO can help achieve more slow doxorubicin (DOX) release and better anti-cancer efficiency than the pristine hydrogel. Combined with the excellent properties mentioned above, we believe that the synthesized GO doped heparin-mimetic hydrogels will have great potential for application in various biomedical fields, such as tissue engineering and implantable drug delivery systems.
Co-reporter:Jie Deng, Xinyue Liu, Shuqing Zhang, Chong Cheng, Chuanxiong Nie, and Changsheng Zhao
Langmuir 2015 Volume 31(Issue 35) pp:9665-9674
Publication Date(Web):August 24, 2015
DOI:10.1021/acs.langmuir.5b02038
Surface modification has long been of great interest to impart desired functionalities to the bioimplants. However, due to the limitations of recent technologies in surface modification, it is highly desirable to explore novel protocols, which can advantageously and efficiently endow the inert material surfaces with versatile biofunctionalities. Herein, to achieve versatile and rapid postfunctionalization of polymeric membrane, we demonstrate a new strategy for the fabrication of β-cyclodextrin (β-CD) modified host membrane substrate that can recognize a series of well-designed guest macromolecules. The surface assembly procedure was driven by the host–guest interaction between adamantane (Ad) and β-CD. β-CD immobilized host membrane was fabricated via two steps: (1) epoxy groups enriched poly(ether sulfone) (PES) membrane was first prepared via in situ cross-linking polymerization and subsequently phase separation; (2) mono-6-deoxy-6-ethylenediamine-β-CD (EDA-β-CD) was then anchored onto the surface of the epoxy functionalized PES membrane to obtain PES-CD. Subsequently, three types of Ad-terminated polymers, including Ad-poly(styrenesulfonate-co-sodium acrylate) (Ad-PSA), Ad-methoxypoly(ethylene glycol) (Ad-PEG), and Ad-poly(methyl chloride-quaternized 2-(dimethylamino)ethyl methacrylate (Ad-PMT), were separately assembled onto the β-CD immobilized surfaces to endow the membranes with anticoagulant, antifouling, and antibacterial capability, respectively. Activated partial thromboplastin time (APTT), thrombin time (TT), and prothrombin time (PT) measurements were carried out to explore the anticoagulant activity. The antifouling capability was evaluated via protein adsorption and platelet adhesion measurements. Moreover, Staphyllococcous aureus (S. aureus) was selected as model bacteria to evaluate the antibacterial ability of the functionalized membranes. The results indicated that well-regulated blood compatibility, antifouling capability, and bactericidal activity could be achieved by the proposed rapid postfunctionalization on polymeric membranes. This approach of versatile and rapid postfunctionalization is promising for the preparation of multifunctional polymeric membrane materials to meet with various demands for the further applications.
Co-reporter:Lingren Wang, Hao Li, Shuai Chen, Chuanxiong Nie, Chong Cheng, and Changsheng Zhao
ACS Biomaterials Science & Engineering 2015 Volume 1(Issue 11) pp:1183
Publication Date(Web):October 12, 2015
DOI:10.1021/acsbiomaterials.5b00320
In this study, we design the interfacial self-assembly of heparin-mimetic multilayer on poly(ether sulfone) (PES) membrane, which can endow the substrate with excellent cytocompatibility, highly hemocompatibility and enhanced antibacterial properties. The coated 3D sponge-like multilayer was fabricated by surface engineered layer by layer assembly of sulfonic amino polyether sulfone (SNPES) and quaternized chitosan (QC). The cell morphology observation and viability evaluation suggested that the assembled multilayer coating had remarkable cytocompatibility with endothelial cells due to the synergistic promotion of bovine serum albumin adsorption and heparin-mimetic groups; which further indicated that surface endothelialization could be achieved on the heparin-mimetic multilayer. The systematical tests of antithrombotic and blood activation indicated that the heparin-mimetic multilayer-coated membrane owned significantly suppressed adsorption of bovine serum fibrinogen, platelet adhesion and activation, prolonged clotting times, as well as lower activation of blood complement. Furthermore, the antibacterial test suggested the multilayer coated substrates exhibited obvious inhibition capability for both Escherichia coli and Staphylococcus aureus. Therefore, we believe that the developed SNPES/QC multilayer on PES membrane show great potential as a multifunctional coating toward versatile biomedical applications due to the integrated and highly effective antithrombotic, endothelialization, and antibacterial properties.Keywords: antibacterial coating; anticoagulant and antithrombotic; endothelialization; heparin-mimetic multilayer; poly(ether sulfone) membrane
Co-reporter:Chuanxiong Nie, Lang Ma, Chong Cheng, Jie Deng, and Changsheng Zhao
Biomacromolecules 2015 Volume 16(Issue 3) pp:
Publication Date(Web):February 10, 2015
DOI:10.1021/bm501882b
Combining the advantages of the fibrous nanostructure of carbon nanotubes (CNTs) and the bioactivities of heparin/heparin-mimicking polyanions, functional nanofibrous heparin or heparin-mimicking multilayers were constructed on PVDF membrane with highly promoted endothelialization and antithrombogenic activities. Oxidized CNT (oCNT) was first functionalized with water-soluble chitosan (polycation), then enwrapped with heparin or a typical sulfonated heparin-mimicking polymers (poly(sodium 4-styrenesulfonate-co-sodium methacrylate)) to construct the multilayers. Then, the surface-deposited multilayers were constructed via electrostatic layer-by-layer assembly of the functionalized oCNTs. The scanning electron microscope and atom force microscope images confirmed that the coated multilayers exhibited nanofibrous and porous structure. The live/dead cell staining and cell viability assay results indicated that the coated nanofibrous multilayers had excellent compatibility with endothelial cells. The cell morphology observation further confirmed the promotion ability of surface endothelialization due to the coated heparin/heparin-mimicking multilayers. Further systematical evaluation on blood compatibility revealed that the surface heparin/heparin-mimicking multilayer-coated membranes also had significantly improved blood compatibility including restrained platelet adhesion and activation, prolonged blood clotting times, and inhibited activation of coagulation and complement factors. In summary, the proposed nanofibrous multilayers integrated endothelialization and antithrombogenic properties; meanwhile, the heparin-mimicking coating validated comparable performances as heparin coating. Herein, it is expected that the surface coating of nanofibrous multilayers, especially the facilely constructed heparin-mimicking coating, may have great application potential in biomedical fields.
Co-reporter:Zehua Yin;Chong Cheng;Hui Qin;Chuanxiong Nie;Chao He
Journal of Biomedical Materials Research Part B: Applied Biomaterials 2015 Volume 103( Issue 1) pp:97-105
Publication Date(Web):
DOI:10.1002/jbm.b.33177
Abstract
Researches on blood purification membranes are fuelled by diverse clinical needs, such as hemodialysis, hemodiafiltration, hemofiltration, plasmapheresis, and plasma collection. To approach high-performance dialyzer, the integrated antifouling and antithrombotic properties are highly necessary for the design/modification of advanced artificial membranes. In this study, we propose and demonstrate that the physical blend of triblock polyurethane (PU) and polyethersulfone (PES) may advance the performance of hemodialysis membranes with greatly enhanced blood compatibility. It was found that the triblock PU could be blended with PES at high ratio owing to their excellent miscibility. The surfaces of the PES/PU composite membranes were characterized using attenuated total reflectance-Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, water contact angle measurement, and surface ζ-potentials. The results indicated that the membrane surfaces were assembled with hydrophilic segregation layer owing to the migration of amphiphilic PU segments during membrane preparation, which might confer the composite membranes with superior hemocompatibility. The cross-section scanning electron microscopy images of the composite membranes exhibited structure transformation from finger-like structure to sponge-like structure, which indicated that the composite membrane had tunable porosity and permeability. The further ultrafiltration experiments indicated that the composite membranes showed increased permeability and excellent antifouling ability. The blood compatibility observation indicated that PES/PU composite membranes owned decreased protein adsorption, suppressed platelet adhesion, and prolonged plasma recalcification time. These results indicated that the PES/PU composite membranes exhibited enhanced antifouling and antithrombotic properties than the pristine PES membrane. The strategy may forward the fabrication of blood compatible composite membranes for clinical blood dialysis by using the various functional miscible polymers. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 97–105, 2015.
Co-reporter:Chong Cheng, Shudong Sun and Changsheng Zhao
Journal of Materials Chemistry A 2014 vol. 2(Issue 44) pp:7649-7672
Publication Date(Web):12 Sep 2014
DOI:10.1039/C4TB01390E
Research into the design of heparin and heparin-like/mimicking polymer-functionalized biomedical membranes is of tremendous interest to the biomedical sector in particular and is driven by potential diverse biomedical applications such as blood purification, artificial organs and other clinical medical devices. In this review, we highlight the progress of the recent research and propose potential biomedical applications in the fields of surface heparinization and the heparin-inspired modification of polymeric membranes. We summarize various surface heparinization strategies such as blending, surface coating, grafting, layer-by-layer assembly and mussel-inspired coating. Then, we classify the heparin-like/mimicking polymers and their applications in the design of heparin-mimicking biomedical membranes and draw some conclusions. The general concept of heparin-like/mimicking polymers is usually defined as heparan sulfates or synthetic sulfated/carboxylated polymers with comparable biologically mimicking functionalities as heparin, especially anticoagulant activity. Moreover, the potential biomedical applications and benefits of heparin and heparin-like/mimicking polymer-functionalized membranes in blood purification, artificial organs and tissue engineering are also discussed in each section. The heparin and heparin-like/mimicking polymer-functionalized membranes presented are exceptional candidates for the treatment of organ failure and many other blood-contacting fields. Finally, we conclude with the challenges and future perspectives for the strategies toward the heparinization and heparin-like/mimicking modification of membrane surfaces. It is believed that this review will evoke more attention towards the design of heparinized and heparin-like/mimicking membranes and encourage future advancements of this emerging research field.
Co-reporter:Lang Ma, Hui Qin, Chong Cheng, Yi Xia, Chao He, Chuanxiong Nie, Lingren Wang and Changsheng Zhao
Journal of Materials Chemistry A 2014 vol. 2(Issue 4) pp:363-375
Publication Date(Web):08 Nov 2013
DOI:10.1039/C3TB21388A
In this study, multifunctional mussel-inspired self-coated membranes with remarkable blood and cell compatibilities are prepared by a facile and green approach. A highly sulfonated linear heparin-like polymer (HepLP, poly(sodium 4-vinylbenzenesulfonate)-co-poly(sodium methacrylate)) and heparin are chosen for the mussel-inspired heparin-mimicking coating, respectively. Firstly, DA is grafted onto the backbone of HepLP or heparin to obtain DA grafted HepLP (DA-g-HepLP) or DA grafted heparin (DA-g-Hep) by means of the carbodiimide chemistry method. Then, the DA-g-HepLP and DA-g-Hep are used to prepare surface coated heparin-mimicking substrates; the polyethersulfone (PES) dialysis membrane is chosen as the model substrate. The coated surface composition, surface morphology, water contact angle, surface zeta-potential, blood compatibility and cell compatibility are systematically investigated. The results of surface spectra, scanning electron microscopy (SEM) and atomic force microscopy (AFM) indicated that the DA-g-HepLP and DA-g-Hep were successfully coated onto the membranes. The coated membranes showed increased hydrophilicity and electronegativity, decreased plasma protein adsorption, and suppressed platelet adhesion compared to the pristine membrane. The cell morphology observation and cytotoxicity assays demonstrated that the surface coated heparin-mimicking membranes showed superior performance in endothelial cell proliferation and morphology differentiation. In addition, the excellent anticoagulant bioactivities indicated that the adhered DA-g-HepLP (or DA-g-Hep) could function or maintain its biological activity after the immobilization. In general, the mussel-inspired protocol of surface self-coating conferred the modified membranes with integrated blood compatibility, cell proliferation and biological activity for multi-biomedical applications, like hemodialysis, blood purification, organ implantation, and cell and tissue cultures.
Co-reporter:Jie Deng, Xinyue Liu, Lang Ma, Chong Cheng, Wenbin Shi, Chuanxiong Nie, and Changsheng Zhao
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 23) pp:21603
Publication Date(Web):November 6, 2014
DOI:10.1021/am506249r
In this study, multifunctional and heparin-mimicking star-shaped supramolecules-deposited 3D porous multilayer films with improved biocompatibility were fabricated via a layer-by-layer (LbL) self-assembly method on polymeric membrane substrates. Star-shaped heparin-mimicking polyanions (including poly(styrenesulfonate-co-sodium acrylate; Star-PSS-AANa) and poly(styrenesulfonate-co-poly(ethylene glycol)methyl ether methacrylate; Star-PSS-EGMA)) and polycations (poly(methyl chloride-quaternized 2-(dimethylamino)ethyl methacrylate; Star-PMeDMA) were first synthesized by atom transfer radical polymerization (ATRP) from β-cyclodextrin (β-CD) based cores. Then assembly of 3D porous multilayers onto polymeric membrane surfaces was carried out by alternating deposition of the polyanions and polycations via electrostatic interaction. The surface morphology and composition, water contact angle, blood activation, and thrombotic potential as well as cell viability for the coated heparin-mimicking films were systematically investigated. The results of surface ATR-FTIR spectra and XPS spectra verified successful deposition of the star-shaped supramolecules onto the biomedical membrane surfaces; scanning electron microscopy (SEM) and atomic force microscopy (AFM) observations revealed that the modified substrate had 3D porous surface morphology, which might have a great biological influence on the biointerface. Furthermore, systematic in vitro investigation of protein adsorption, platelet adhesion, human platelet factor 4 (PF4, indicates platelet activation), activate partial thromboplastin time (APTT), thrombin time (TT), coagulation activation (thrombin-antithrombin III complex (TAT, indicates blood coagulant)), and blood-related complement activation (C3a and C5a, indicates inflammation potential) confirmed that the heparin-mimicking multilayer coated membranes exhibited ultralow blood component activations and excellent hemocompatibility. Meanwhile, after surface coating, endothelial cell viability was also promoted, which indicated that the heparin-mimicking multilayer coating might extend the application fields of polymeric membranes in biomedical fields.Keywords: blood and cell compatibility; heparin-mimicking multilayer; layer-by-layer assembly; polymeric membranes; star-shaped supramolecules; β-cyclodextrin
Co-reporter:Yi Xia, Chong Cheng, Rui Wang, Hui Qin, Yi Zhang, Lang Ma, Hong Tan, Zhongwei Gu and Changsheng Zhao
Polymer Chemistry 2014 vol. 5(Issue 20) pp:5906-5919
Publication Date(Web):08 Jul 2014
DOI:10.1039/C4PY00870G
In this study, novel 3D multifunctional nanolayers are fabricated on biomedical membrane surfaces via layer-by-layer (LBL) self-assembly of nanogels and heparin-like polymers. To integrate long-term antibacterial activity, Ag nanoparticles embedded in nanogels were first prepared. Then, the Ag nanogels were assembled onto membrane surfaces by electrostatic interaction. To obtain a heparin-mimicking surface, the as-prepared nanogel-coated membranes were further assembled with heparin-like polymers by two different processes. The results indicated that the obtained nanogel and heparin-mimicking polymer assembled membranes exhibited 3D surface morphologies. Systematical blood compatibility and antithrombotic evaluations revealed that the functionalized membranes showed increased hydrophilicity, decreased protein adsorption, and prolonged clotting times and greatly suppressed platelet adhesion compared to pristine membrane. The cell culture observations demonstrated that the pristine, nanogel-assembled, and heparin-mimicking membranes showed different performances in terms of endothelial cell proliferation and adhesion morphology. The results of the antibacterial study indicated that the functionalized membranes exhibited significant inhibition capability for Escherichia coli and Staphylococcus aureus. In general, the surface coassembly of nanogels and heparin-mimicking polymers produced functionalized membranes with integrated blood compatibility, cell proliferation and antibacterial properties for multiple applications, which may advance the fabrication of biomedical devices by surface assembly of functional nanogels.
Co-reporter:Hongju Zhou, Chong Cheng, Hui Qin, Lang Ma, Chao He, Shengqiang Nie, Xiang Zhang, Qiang Fu and Changsheng Zhao
Polymer Chemistry 2014 vol. 5(Issue 11) pp:3563-3575
Publication Date(Web):18 Feb 2014
DOI:10.1039/C4PY00136B
Research on the interface self-assembly of functional layers is fuelled by diverse biomedical needs, like drug encapsulation and release, stem cell proliferation and differentiation, cell and tissue cultures, as well as artificial organs. In this study, a novel and biocompatible 3D composite layer is fabricated on a membrane substrate by the layer-by-layer (LBL) self-assembly of graphene-based 2D supermolecules. The graphene-based 2D supermolecules are prepared by grafting poly(styrenesulfonate) (PSS, polyanion) and poly(acrylamide) (PAM, polycation) onto graphene oxide (GO) through free radical polymerization. Then, the prepared graphene-based supermolecules are taken to construct a 3D porous thin film layer through a LBL process. Polyethersulfone (PES) membrane is chosen as the model substrate. The chemical composition, surface morphology, water contact angle, surface zeta-potential, blood compatibility and the cell compatibility are systematically investigated. The results indicate that the 2D graphene-based supermolecules are successfully assembled into a 3D porous thin film layer structure on the membrane surface. The assembled layer shows increased hydrophilicity, suppressed platelet adhesion, and a limited hemolysis ratio and complement activation compared to the pristine substrate. The cell morphology observation and cytotoxicity assays demonstrate that the 3D graphene layer shows superior performance both in endothelial and hepatocyte cells proliferation and morphology differentiation. In addition, the excellent anticoagulant bioactivities indicate that the 2D graphene-based supermolecules have heparin-mimicking biological activity. In general, the protocol of interface thin film layer self-assembly confers the modified substrates with integrated blood compatibility, cell proliferation and biological activity; which may forward the fabrication of multi-functional biomedical devices by using the 2D graphene-based supermolecules.
Co-reporter:Shengqiang Nie, Min Tang, Chong (Sage) Cheng, Zehua Yin, Lingren Wang, Shudong Sun and Changsheng Zhao
Biomaterials Science 2014 vol. 2(Issue 1) pp:98-109
Publication Date(Web):17 Sep 2013
DOI:10.1039/C3BM60165J
In the present work, inspired by the chemical structure of heparin molecules, we designed a polyethersulfone (PES) membrane with a heparin-like surface for the first time by physically blending sulfonated polyethersulfone (SPES), carboxylic polyethersulfone (CPES), and PES at rational ratios. Evaporation and phase-inversion membranes of PES/CPES/SPES were prepared by evaporating the solvent in a vacuum oven, and by a liquid–liquid phase separation technique, respectively. Scanning electron microscopy (SEM) images revealed that the structures of the PES/CPES/SPES membranes were dependent on the proportions of the additives and no obvious phase separation was detected. The blood compatibility of the modified membrane surfaces was characterized in terms of bovine serum fibrinogen (BFG) adsorption, platelet adhesion, thrombin–antithrombin (TAT) generation, percentage of platelets positive for CD62p expression, clotting times (activated partial thromboplastin time (APTT) and prothrombin time (PT)), and complement activation on C3a and C5a levels. The results indicated that the blood compatibility of PES matrix was improved due to the biologically inspired membrane design with a heparin-like interface by introducing functional sulfonic acid and carboxylic acid groups. Furthermore, cell morphology observation and cell culture assays demonstrated that the modified membranes showed better performance in bio-artificial liver related cell proliferation than the pristine PES membrane. In general, the intriguing PES/CPES/SPES membranes, especially the phase-inversion one, showed improved blood and cell compatibility, which might have great potential application in the blood purification field.
Co-reporter:Fen Ran, Xiaoqin Niu, Haiming Song, Chong (Sage) Cheng, Weifeng Zhao, Shengqiang Nie, Lingren Wang, Aimei Yang, Shudong Sun and Changsheng Zhao
Biomaterials Science 2014 vol. 2(Issue 4) pp:538-547
Publication Date(Web):08 Jan 2014
DOI:10.1039/C3BM60250H
Comb-like amphiphilic copolymers (CLACs) consisting of functional chains of poly(vinyl pyrrolidone) and polyethersulfone-based hydrophobic chains were firstly synthesized by reversible addition–fragmentation chain transfer polymerization. The CLAC can be used as an additive to blend with polyethersulfone (PES) at any ratio due to the excellent miscibility, and then a surface segregation layer with permanent hydrophilicity could be obtained. The surfaces of the CLAC modified PES membranes were characterized using X-ray photoelectron spectroscopic analysis, Fourier transform infrared and water contact angle measurements. The surfaces are self-assembled with numerous functional branch-like –PVP chains, which can improve the hemocompatibility. The root-like –PES chains (the hydrophobic part) are embedded in the membranes firmly, which greatly reduces the elution during the membrane preparation procedure and repeated usage, and makes the membranes have a permanent stability. The PES-based hydrophobic chains have the same structure as the membrane bulk material, which makes the miscibility of the additive and the membrane material good to ensure the intrinsic properties of the membrane. The modified membranes showed suppressed platelet adhesion and prolonged blood coagulation time (activated partial thromboplastin time, APTT); thus, the blood compatibility of the membranes was highly improved. The strategy may be extended to synthesize other PES-based functional copolymers and to prepare a modified PES dialysis membrane for blood purification.
Co-reporter:Chong Cheng, Zhengyang Liu, Xiaoxiao Li, Baihai Su, Tao Zhou and Changsheng Zhao
RSC Advances 2014 vol. 4(Issue 80) pp:42346-42357
Publication Date(Web):29 Aug 2014
DOI:10.1039/C4RA07114J
Recent studies showed that polymeric hydrogels presented promising applications in adsorption to various water contaminants. However, the usages of these synthetic hydrogels are hindered by several inherent shortages, e.g. limited inner porosity, low adsorption capacity and long equilibrium time. In this study, synthetic GO interpenetrated poly(acrylic acid) (PAA) hydrogels as 3D highly-efficient adsorbents were prepared and systematically studied for the first time. The mediating ability of GO on the inner structure and adsorption capacities is examined using two types of PAA hydrogels (PAA1 and PAA2 with different inner structures, prepared by in situ cross-linked polymerization of monomer AA). The results indicated that the prepared PAA2/GO hydrogels exhibited a well-defined and interconnected 3D porous network, which allowed the adsorbate molecules to diffuse easily into the absorbent. The adsorption experiments indicated that the obtained interconnected polymeric composite hydrogels could efficiently remove cationic dyes and heavy metal ions from wastewater; the highest adsorption capacity of the prepared PAA2/GO composite hydrogels could reach as high as 1600 mg g−1, which is highly promising in the treatment of environmental toxins. Moreover, the initial concentration, pH value, desorption ratio, dynamic kinetics and isotherms of the methylene blue (MB) adsorption processes of the prepared PAA2/GO composite hydrogels were also studied in detail. The experimental data of MB adsorption fitted the pseudo-second-order kinetic model and the Langmuir isotherm very well, and the adsorption process was controlled by the intraparticle diffusion. Moreover, due to its facile preparation and low-cost, the GO interpenetrated PAA composite hydrogels may function as promising adsorbents for wastewater treatment, and this method might also be extended to improve the adsorption capacity of other polymeric hydrogels.
Co-reporter:Hui Qin;Shengqiang Nie;Chong Cheng;Fen Ran;Chao He;Lang Ma;Zehua Yin
Polymers for Advanced Technologies 2014 Volume 25( Issue 8) pp:851-860
Publication Date(Web):
DOI:10.1002/pat.3316
Applications of blood purification membranes are fuelled by diverse clinical needs, such as hemodialysis, hemodiafiltration, hemofiltration, plasmapheresis, and plasma collection. For clinical usage, the adding of polyvinylpyrrolidone (PVP) is the general protocol for the design of antifouling and antithrombotic properties integrated artificial membranes. In the present work, to insight into the detailed surface properties and blood compatibilities of the PVP blended composite membranes, we synthesized a series of PVP polymers with different molecular weights using reversible addition fragmentation chain transfer polymerization and designed a series of polyethersulfone (PES)/PVP composite membranes by a physically blending method. The effects of PVP molecular weights and blending ratios on the surface properties and the blood compatibilities of the composite membranes were investigated in detail. The surface attenuated total reflection Fourier transform infrared spectra and scanning electron microscopy pictures indicated that the PVP was successfully immobilized into the membranes, and the composite membranes exhibited morphology transformation from finger-like structure to sponge-like structure, which indicated that the composite membrane had tunable porosity and permeability by adding PVP. The blood compatible tests revealed that the composite membranes showed increased hydrophilicity, decreased plasma protein adsorption, suppressed platelet adhesion, and prolonged blood clotting time compared with pristine PES membrane. These results indicated that the PES/PVP composite membranes exhibited enhanced antifouling and antithrombotic properties than the pristine PES membrane. Meanwhile, the results also suggested that the composite membranes with larger molecular weight PVP and higher blending ratios might show better blood compatibility. Copyright © 2014 John Wiley & Sons, Ltd.
Co-reporter:Tao Xiang, Yi Xie, Rui Wang, Ming-Bang Wu, Shu-Dong Sun, Chang-Sheng Zhao
Materials Letters 2014 Volume 137() pp:192-195
Publication Date(Web):15 December 2014
DOI:10.1016/j.matlet.2014.09.037
•Surface chemical modification was carried out on the membrane surface.•–OH, –N3, –NH2, –COOH and –SO3H were introduced onto the polysulfone membrane.•The hydrophilicity of the –OH, –COOH and –SO3H grafted membranes were increased.•The anticoagulant property of the –COOH and –SO3H modified membranes was improved.Polysulfone (PSf) membrane has been widely used in biomedical fields. In this study, we report the modification of PSf membrane via surface chemical reactions to improve the hydrophilicity and blood compatibility, and the modification is based on chloromethylated PSf (PSf-Cl) membrane. Different functional groups, including hydroxyl groups (–OH), azide groups (–N3), amine groups (–NH2), carboxyl groups (-COOH) and sulfo groups (–SO3H) were introduced onto the PSf membrane surfaces, and the modified membranes showed obviously improved hydrophilicity. Meanwhile, the blood compatibility was also investigated, and the –COOH and –SO3H grafted membranes exhibited improved anticoagulant property.
Co-reporter:Tao Xiang, Rui Wang, Wei-Feng Zhao, Shu-Dong Sun, and Chang-Sheng Zhao
Langmuir 2014 Volume 30(Issue 18) pp:5115-5125
Publication Date(Web):2017-2-22
DOI:10.1021/la5001705
Development of blood compatible membranes is critical for biomedical applications. Zwitterionic polymers have been proved to be resistant to nonspecific protein adsorption and platelet adhesion. In this work, two kinds of zwitterionic copolymers bearing alkynyl and azide groups are synthesized by atom transfer radical polymerization (ATRP) and subsequent reactions, namely alkynyl-poly(sulfobetaine methacrylate) (alkynyl-PSBMA) and azide-poly(sulfobetaine methacrylate) (azide-PSBMA). The copolymers are directly used to modify azido-functionalized polysulfone (PSf-N3) membrane via click chemistry-enabled layer-by-layer (LBL) assembly. Alkynyl-citric acid is then clicked onto the membrane when the outermost layer was azide-PSBMA. The chemical compositions, surface morphologies, and hydrophilicity of the zwitterionic polymer and citric acid multilayer modified membranes are characterized. The composite multilayer is resistant to protein adsorption and platelet adhesion and also prolongs clotting times, indicating that the blood compatibility is improved. Moreover, after clicking the small molecule anticoagulant alkynyl-citric acid onto the outermost of the zwitterionic multilayer, the membrane shows further improved anticoagulant property. The deposition of zwitterionic polymer and citric acid via click chemistry-enabled LBL assembly can improve the blood compatibility of the PSf membrane.
Co-reporter:Wen Zou, Hui Qin, Wenbin Shi, Shudong Sun, and Changsheng Zhao
Langmuir 2014 Volume 30(Issue 45) pp:13622-13630
Publication Date(Web):October 27, 2014
DOI:10.1021/la502343c
In this study, we provide a new method to modify poly(ether sulfone) (PES) membrane with good biocompatibility, for which diazotized PES (PES-N2+) membrane is covalently coated by a negatively charged copolymer of sodium sulfonated poly(styrene-alt-maleic anhydride) (NaSPS-MA). First, aminated PES (PES-NH2) is synthesized by nitro reduction reaction of nitro-PES (PES-NO2), and then blends with pristine PES to prepare PES/PES-NH2 membrane; then the membrane is treated with NaNO2 aqueous solution at acid condition; after surface diazo reaction, surface positively charged PES/PES-N2+ membrane is prepared. Second, poly(styrene-alt-maleic anhydride) (PS-alt-MA) is synthesized, then sulfonated and treated by sodium hydroxide solution to obtain sodium sulfonated (PS-alt-MA) (NaSPS-MA). Finally, the negatively charged NaSPS-MA copolymer is coated onto the surface positively charged PES/PES-N2+ membrane via electrostatic interaction; after UV-cross-linking, the linkage between the PES-N2+ and NaSPS-MA changes to a covalent bond. The surface-modified PES membrane is characterized by FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS) analyses, and surface zeta potential analyses. The modified membrane exhibits good hemocompatibility and cytocompatibility, and the improved biocompatibility might have resulted from the existence of the hydrophilic groups (sodium carboxylate (−COONa) and sodium sulfonate (−SO3Na)). Moreover, the stability of the modified membrane is also investigated. The results indicated that the modified PES membrane using negatively charged copolymers had a lot of potential in blood purification fields and bioartificial liver supports for a long time.
Co-reporter:Xinyue Liu, Jie Deng, Lang Ma, Chong Cheng, Chuanxiong Nie, Chao He, and Changsheng Zhao
Langmuir 2014 Volume 30(Issue 49) pp:14905-14915
Publication Date(Web):2017-2-22
DOI:10.1021/la503872h
In this study, we proposed a catechol chemistry inspired approach to construct surface self-cross-linked polymer nanolayers for the design of versatile biointerfaces. Several representative biofunctional polymers, P(SS-co-AA), P(SBMA-co-AA), P(EGMA-co-AA), P(VP-co-AA), and P(MTAC-co-AA), were first synthesized via reversible addition–fragmentation chain transfer (RAFT) polymerization, and then the catecholic molecules (dopamine, DA) were conjugated to the acrylic acid (AA) units by the facile carbodiimide chemistry. Then, the catechol (Cat) group conjugated biofunctional polymers, named PSS-Cat, PSBMA-Cat, PEGMA-Cat, PVP-Cat, and PMTAC-Cat, were applied for the construction of self-cross-linked nanolayers on polymeric substrates via the pH induced catechol cross-linking and immobilization. The XPS spectra, surface morphology, and wettability gave robust evidence that the catechol conjugated polymers were successfully coated, and the coated substrates possessed increased surface roughness and hydrophilicity. Furthermore, the systematic in vitro investigation of protein adsorption, platelet adhesion, activated partial thromboplastin time (APTT), thrombin time (TT), cell viability, and antibacterial ability confirmed that the coated nanolayers conferred the substrates with versatile biological performances. The PSS-Cat coated substrate had low blood component activation and excellent anticoagulant activity; while the PEGMA-Cat and PSBMA-Cat showed ideal resistance to protein fouling and inhibition of platelet activation. The PSS-Cat and PVP-Cat coated substrates exhibited promoted endothelial cell proliferation and viability. The PMTAC-Cat coated substrate showed an outstanding activity on bacterial inhibition. In conclusion, the catechol chemistry inspired approach allows the self-cross-linked nanolayers to be easily immobilized on polymeric substrates with the stable conformation and multiple biofunctionalities. It is expected that this low-cost and facile bioinspired coating system will present great potential in creating novel and versatile biointerfaces.
Co-reporter:Chong Cheng, Shengqiang Nie, Shuang Li, Hong Peng, Hang Yang, Lang Ma, Shudong Sun and Changsheng Zhao
Journal of Materials Chemistry A 2013 vol. 1(Issue 3) pp:265-275
Publication Date(Web):19 Sep 2012
DOI:10.1039/C2TB00025C
A green and facile method for preparing biopolymer functionalized reduced graphene oxide (RGO) by using mussel inspired dopamine (DA) as the reducing reagent and the functionalized molecule is proposed. In the study, GO is reduced by DA and DA is adhered to RGO by one-step pH-induced polymerization of DA (polydopamine, PDA), and then heparin or protein is grafted onto the PDA adhered RGO (pRGO) through catechol chemistry. The obtained pRGO, heparin grafted pRGO (Hep-g-pRGO), and BSA grafted pRGO (BSA-g-pRGO) exhibit fine 2D morphology and excellent stability in water and PBS solution. Furthermore, the biocompatibility of the biopolymer functionalized RGO are investigated using human blood cells and human umbilical vein endothelial cells (HUVECs). The biopolymer functionalized RGO exhibits an ultralow hemolysis ratio (lower than 1.8%), and the cellular toxicity assay suggests that the biopolymer functionalized RGO has good cytocompatibility for HUVEC cells, even at a high concentration of 100 μg mL−1. Moreover, the high anticoagulant ability of Hep-g-pRGO indicates that the grafted biopolymer could maintain its biological activity after immobilization onto the surface of pRGO. Therefore, the proposed safe and green biomimetic method confers the biopolymer functionalized RGO with great potential for various biological and biomedical applications.
Co-reporter:L.R. Wang, H. Qin, S.Q. Nie, S.D. Sun, F. Ran, C.S. Zhao
Acta Biomaterialia 2013 Volume 9(Issue 11) pp:8851-8863
Publication Date(Web):November 2013
DOI:10.1016/j.actbio.2013.07.010
Abstract
In this study, heparin-like poly(ethersulfone) (HLPES) was synthesized by a combination of polycondensation and post-carboxylation methods, and was characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance hydrogen spectrum and gel permeation chromatography. Owing to the similar backbone structure, the synthesized HLPES could be directly blended with pristine PES at any ratios to prepare PES/HLPES membranes. After the introduction of HLPES, the microscopic structure of the modified PES membranes was changed, while the hydrophilicity was significantly enhanced. Bovine serum albumin and bovine serum fibrinogen adsorption, activated partial thromboplastin time, thromb time and platelet adhesion for the modified PES membranes were investigated. The results indicated that the blood compatibility of the PES/HLPES membranes was significantly improved compared with that of pristine PES membrane. For the PES/HLPES membranes, obvious decreases in platelet activation on PF-4 level, in complement activation on C3a and C5a levels, and in leukocytes activation on CD11b levels were observed compared with those for the pristine PES membrane. The improved blood compatibility of the PES/HLPES membrane might due to the existence of the hydrophilic groups (–SO3Na, –COONa). Furthermore, the modified PES membranes showed good cytocompatibility. Hepatocytes cultured on the PES/HLPES membranes presented improved growth in terms of SEM observation, MTT assay and confocal laser scanning microscope observation compared with those on the pristine PES membrane. These results indicate that the PES/HLPES membranes present great potential in blood-contact fields such as hemodialysis and bio-artificial liver supports.
Co-reporter:Weifeng Zhao, Quanbing Mou, Xiaoxue Zhang, Jingyu Shi, Shudong Sun, Changsheng Zhao
European Polymer Journal 2013 Volume 49(Issue 3) pp:738-751
Publication Date(Web):March 2013
DOI:10.1016/j.eurpolymj.2012.11.018
Sulfonated polyethersulfone (SPES) was synthesized through a feasible way by introducing sulfonic groups onto amino-substituted PES, and characterized by FT-IR, 1H NMR and GPC. The obtained SPES could be directly blended with PES at any ratios to prepare modified membranes. Scanning electron microscope indicated that the structure of the PES membranes had an obvious change after the modification. The water contact angles of the modified PES membranes decreased from 84° to 68°, and the water fluxes had a dramatic increase from 162 to 1912 mL/m2 mmHg h when the blended amount of SPES increased from 0 to 2 wt.%. The activated partial thromboplastin time and plasma recalcification time for the modified membranes increased significantly, and the blood platelet adhesion on the PES membrane was largely suppressed after the modification. All these results indicated that the hydrophilicity and the anticoagulant activity of the modified PES membranes were improved, and the modified membranes had a potential to be used in blood purification fields.Graphical abstractHighlights► An ease method for fabricate sulfonated polyethersulfone (SPES) was provided. ► The side reactions and degradation reactions could be avoidable in this approach. ► The obtained SPES could be directly blended with PES in a large range of ratios. ► The anticoagulant activity of the membranes was significantly improved. ► The method employed in this study can be used to modify other polymeric membranes.
Co-reporter:Tao Xiang, Wen-Wen Yue, Rui Wang, Su Liang, Shu-Dong Sun, Chang-Sheng Zhao
Colloids and Surfaces B: Biointerfaces 2013 110() pp: 15-21
Publication Date(Web):
DOI:10.1016/j.colsurfb.2013.04.034
Co-reporter:Chong Cheng, Shuang Li, Weifeng Zhao, Qiang Wei, Shengqiang Nie, Shudong Sun, Changsheng Zhao
Journal of Membrane Science 2012 Volumes 417–418() pp:228-236
Publication Date(Web):1 November 2012
DOI:10.1016/j.memsci.2012.06.045
In this paper, the characters of hydrodynamic permeability, surface property, and blood compatibility of polydopamine (PDA) coated polyethersulfone (PES) ultrafiltration (UF) membranes were investigated in detail. We presented a general protocol to improve the hydrodynamic permeability and blood compatibility of PES UF membranes by a simple biomimetic strategy. The chemical structure and surface morphology of the PDA coated membranes were studied in detail; meanwhile, the influence of the coated PDA nano-layer on water contact angle and water flux of the modified membranes was investigated. It was found that the water flux of the pure PES membrane decreased dramatically, approach to 0 ml/(m2 h mmHg), after a few hours of PDA coating. To avoid the dramatic decline of water flux, the method of pre-adding pore-forming reagent was taken to fabricate the PDA coated PES membranes with tunable water flux. Moreover, the anti-fouling property, platelet adhesion, and blood coagulation time of the PDA modified PES membranes were studied, and the results indicated that the PDA modified PES UF membranes showed enhanced blood compatibility.Graphical abstractHighlights► Polydopamine was used to improve hydrophilicity and hemocompatibility of PES membrane. ► The chemical structure and surface morphology of the coated PDA layer were studied. ► The modified membranes showed enhanced anti-fouling ability and blood compatibility.
Co-reporter:Lulu Li, Chong Cheng, Tao Xiang, Min Tang, Weifeng Zhao, Shudong Sun, Changsheng Zhao
Journal of Membrane Science 2012 Volumes 405–406() pp:261-274
Publication Date(Web):1 July 2012
DOI:10.1016/j.memsci.2012.03.015
Citric acid, a widely used anticoagulant, was grafted onto polyurethane through a two-step solution polymerization. The novel synthesized polymer can be directly blended with polyethersulfone (PES) to prepare membranes. The modified membranes showed lower protein (bovine serum albumin, BSA; bovine serum fibrinogen, BFG) adsorption and suppressed platelet adhesion. Due to the binding of calcium ions in blood, the modified membranes effectively prolonged the activated partial thromboplastin time (APTT), prothrombin time (PT), plasma recalcification time (PRT) and the whole blood clotting time (WBCT). Furthermore, the modified membranes showed good cytocompatibility, and the surfaces promoted hepatocyte adhesion and proliferation compared to pure PES membrane. These results indicated that the surface modification by blending citric acid grafted polyurethane provided practical application of the membranes with good biocompatibility, especially the anticoagulant property; and the membranes could be used in blood purification fields, such as hemodialysis and bioaritificial liver assist devices.Highlights► Citric acid was grafted onto polyurethane, used as the anticoagulant additive. ► A new activated partial thromboplastin time method was introduced in this paper. ► The blood compatibility and cytocompatibility of the blended membrane were researched.
Co-reporter:Min Tang, Jimin Xue, Kelin Yan, Tao Xiang, Shudong Sun, Changsheng Zhao
Journal of Colloid and Interface Science 2012 Volume 386(Issue 1) pp:428-440
Publication Date(Web):15 November 2012
DOI:10.1016/j.jcis.2012.07.076
Sulfonated polyethersulfone (SPES) and poly (acrylonitrile-co-acrylic acid-co-vinyl pyrrolidone) (P(AN–AA–VP)), which provided sulfonic acid (SO3H) and carboxylic acid groups (COOH), respectively, were used to modify polyethersulfone (PES) membrane with a heparin-like surface by blending method. The SPES was prepared by sulfonation of PES using chlorosulfonic acid as the sulfonating agent, while the P(AA–AN–VP) was prepared through a free radical polymerization. The PES and modified PES membranes were prepared by a phase-inversion technique; the modified membranes showed lowered protein (bovine serum albumin, BSA; bovine serum fibrinogen, FBG) adsorption and suppressed platelet adhesion. For the modified membranes, significant decreases in thrombin–antithrombin (TAT) generation, percentage platelets positive for CD62p expression, and the complement activation on C3a and C5a levels were observed compared with those for the pure PES membrane. Due to the similar negatively charged groups as heparin, the modified membranes effectively prolonged the activated partial thromboplastin time (APTT). Furthermore, the modified membranes showed good cytocompatibility. Hepatocytes cultured on the modified materials exhibited improved functional profiles in terms of scanning electron microscope (SEM) observation and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay compared with those on the pure PES membrane. It could be concluded that the modified membranes with sulfonic acid and carboxylic acid groups were endowed with excellent biocompatibility, and the heparin-like surface modification seemed to be a promising approach to improve the biocompatibility of materials.Graphical abstractHighlights► Heparin-like structure surface was introduced into polyethersulfone membrane. ► The membrane characterization was studied upon ATR–FTIR, 1H NMR and SEM. ► Heparin-like membrane show highly improved biocompatibility. ► Biocompatibility could be improved by the heparin-like modification method.
Co-reporter:Lulu Li;Tao Xiang;Baihai Su;Huijuan Li;Bosi Qian
Journal of Applied Polymer Science 2012 Volume 123( Issue 4) pp:2320-2329
Publication Date(Web):
DOI:10.1002/app.34902
Abstract
In our recent study, pH-sensitive polyethersulfone (PES) hollow fiber membranes were prepared by blending poly (acrylonitrile-co-acrylic acid) (PANAA), and the electroviscous effect had great effect on the water flux change. While the question remains: is the water flux change caused by the electroviscous effect for all the membranes with different pore sizes? Herein, pH-sensitive hollow fiber membranes with different pore sizes were prepared. The pore size and the theoretic water flux were calculated through the ultrafiltration of polyethylene glycol (PEG) solution. Comparing the calculated fluxes and the experimental ones, we found that the water flux change was mainly caused by the pore size change at the pH value larger than pKa, while that was caused by both the pore size change and the electroviscous effect when pH value was smaller than the pKa, and the pore size change was caused by the ionization of the COOH in the copolymer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Co-reporter:Bai-Hai Su;Yunying Shi;Ping Fu;Ye Tao;Shengqiang Nie;Chang-Sheng Zhao
Journal of Applied Polymer Science 2012 Volume 124( Issue S1) pp:E91-E98
Publication Date(Web):
DOI:10.1002/app.35589
Abstract
In this study, the blood compatibility and performance of a new polyethersulfone (PES) high-flux hemodialysis membrane were clinically investigated, and compared with two commercial high-flux membranes, polysulfone (PSF) and polyamide (PA) membranes. The structure of the membranes was observed by scanning electron microscopy, and the membrane structure showed significant difference among the three membranes. However, there was no significant difference (no statistical difference, P > 0.05) in the solute clearance and the reduction ratio for small molecules (urea, creatinine, and phosphate) and middle molecule β2-microglobulin. The changes of total bilirubin (TBIL) and aspartate aminotransferase (AST) for the PES and PSF membranes showed no significant differences, both the TBIL and DBIL levels slightly increased compared to the initial levels. However, for the PA membrane, the TBIL and AST levels decreased obviously. The PES hollow fiber membrane hemodialyzer was effective and safe for the treatment of uremic patients, and the performances of PES, PSF and PA high-flux hemodialysis membranes are comparable. The PES and PSF membranes showed similar blood compatibility and solute clearance, and might be better than the PA membrane. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Co-reporter:Dongsheng Wang;Beijia Li;Weifeng Zhao;Yi Lu;Shudong Sun
Journal of Applied Polymer Science 2012 Volume 126( Issue 4) pp:1277-1290
Publication Date(Web):
DOI:10.1002/app.36630
Abstract
Carboxylic poly(ether sulfone) membranes were prepared by a controlled acetylating and surface-oxidating reaction followed by the grafting of bovine serum albumin (BSA) and bovine serum fibrinogen (BFG) onto the surfaces. Attenuated total reflection–Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Micro BCA Protein Assay Kits confirmed that the proteins were successfully grafted onto the surfaces of the membranes. The protein grafting degrees were measured at different time intervals and under different conditions. The modified membranes showed higher hydrophilicity, lower protein (BSA and BFG) adsorption, and suppressed platelet adhesion values. Because of the binding of calcium ions in blood, the modified membranes showed longer plasma recalcification times, activated partial thromboplastin times, prothrombin times, and whole blood clotting times. The results indicate that the blood compatibility of the poly (ether sulfone) membranes could be improved after surface carboxylic modification and protein immobilization and that the modified membranes could be used in the blood purification field. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Co-reporter:Zehua Yin;Baihai Su;Shengqiang Nie;Dongsheng Wang;Shudong Sun
Fibers and Polymers 2012 Volume 13( Issue 3) pp:269-276
Publication Date(Web):2012 March
DOI:10.1007/s12221-012-0269-7
In this study, poly (vinylpyrrolidone-acrylonitrile-vinylpyrrolidone) (PVP-AN-VP) was synthesized by three-step solution free radical polymerization. The copolymer could be directly blended with polyethersulfone (PES) using NMP as a solvent, and then PES hollow fiber membrane was prepared by using dry-wet spinning technique based on a liquid-liquid phase separation technique. Adding the copolymer could effectively reduce the BSA adsorption and suppress the platelet adhesions. Meantime, the antifouling property of the membranes increased with the increase of the copolymer amounts. Furthermore, activated partial thromboplastin time (APTT) of the modified PES hollow fiber membrane increased by 50 % compared to that of pure PES membrane. The efficient surface modification by blending PVP-AN-VP copolymer suggested that the modified PES membrane have potential to be used in blood purification fields.
Co-reporter:Shengqiang Nie, Jimin Xue, Yi Lu, Yeqiu Liu, Dongsheng Wang, Shudong Sun, Fen Ran, Changsheng Zhao
Colloids and Surfaces B: Biointerfaces 2012 100() pp: 116-125
Publication Date(Web):
DOI:10.1016/j.colsurfb.2012.05.004
Co-reporter:Dongsheng Wang, Xiaoxue Zhang, Shengqiang Nie, Weifeng Zhao, Yi Lu, Shudong Sun, and Changsheng Zhao
Langmuir 2012 Volume 28(Issue 37) pp:13284-13293
Publication Date(Web):August 15, 2012
DOI:10.1021/la302687d
In the present study, photoresponsive surface molecularly imprinted poly(ether sulfone) microfibers are prepared via nitration reaction, the wet-spinning technique, surface nitro reduction reaction, and surface diazotation reaction for the selectively photoregulated uptake and release of 4-hydrobenzoic acid. The prepared molecularly imprinted microfibers show selective binding to 4-HA under irradiation at 450 nm and release under irradiation at 365 nm. The simple, convenient, effective, and productive method for the preparation of azo-containing photoresponsive material is also applied to the modification of polysulfone and poly(ether ether ketone). All three benzene-ring-containing polymers show significant photoresponsibility after the azo modification.
Co-reporter:Changsheng Zhao, Shengqiang Nie, Min Tang, Shudong Sun
Progress in Polymer Science 2011 Volume 36(Issue 11) pp:1499-1520
Publication Date(Web):November 2011
DOI:10.1016/j.progpolymsci.2011.05.004
Significant progress has been achieved in recent years in the field of pH-sensitive membranes. In many cases, pH-sensitive membranes are systems for which the flux, membrane pore size, and solute rejection ratio may be manipulated by changing the pH. This review summarizes recent developments covering the preparation, pH-responsive properties, and applications in various disciplines. The pH-sensitive groups and the evaluation parameters for pH-sensitive membranes are reviewed and discussed. A variety of preparation methodologies, including blending, pore-filling, surface-grafting, and surface-coating techniques are described, and some of their salient features are highlighted. The flat-sheet form and hollow-fiber form pH-sensitive membranes are reviewed. Membrane pore size change and electroviscous effect are discussed. Furthermore, future perspectives of pH-sensitive membranes are discussed.
Co-reporter:Weifeng Zhao, Jingyun Huang, Baohong Fang, Shengqiang Nie, Nan Yi, Baihai Su, Haifeng Li, Changsheng Zhao
Journal of Membrane Science 2011 Volume 369(1–2) pp:258-266
Publication Date(Web):1 March 2011
DOI:10.1016/j.memsci.2010.11.065
The present methodology provides a simple approach to prepare semi-interpenetrating network (semi-IPN) polymeric nanoparticles for the modification of polyethersulfone (PES) membranes. The PES/poly (N-vinyl pyrrolidinone) (PVP) semi-IPN nanoparticles were synthesized by cross-linking VP on PES chains via solution polymerization; the size of the nanoparticles ranged from 38 to 820 nm determined by dynamic light scattering (DLS), scanning electron microscope (SEM) and transmission electron microscope (TEM). The polymeric nanoparticles could be directly used to prepare membranes, and the membranes were characterized by SEM, elemental analysis etc. The water contact angles of the PES membranes decreased from 74° to 53°, and the adsorbed protein amount decreased from 9.5 μg/cm2 to 0.7 μg/cm2; meanwhile the water flux and protein anti-fouling property of the membranes increased significantly. The activated partial thrombin time (APTT) of the modified membrane was prolonged. All these results indicated the hydrophilicity and the blood compatibility of the modified PES membranes were improved.Research highlights▶ An ease method for the fabrication of semi-IPN polymeric nanoparticles was reported. ▶ The nanoparticles could be directly used for the modification of PES membranes. ▶ The hydrophilicity and the blood compatibility of the membranes were improved. ▶ The method employed in this study can also be used to modify other type of membranes.
Co-reporter:Fen Ran, Shengqiang Nie, Weifeng Zhao, Jie Li, Baihai Su, Shudong Sun, Changsheng Zhao
Acta Biomaterialia 2011 Volume 7(Issue 9) pp:3370-3381
Publication Date(Web):September 2011
DOI:10.1016/j.actbio.2011.05.026
Abstract
An amphiphilic triblock co-polymer of poly(vinyl pyrrolidone)–b-poly(methyl methacrylate)–b-poly(vinyl pyrrolidone) (PVP-b-PMMA-b-PVP) was synthesized via reversible addition–fragmentation chain transfer (RAFT) polymerization. The block co-polymer can be directly blended with polyethersulfone (PES) using dimethylacetamide (DMAC) as the solvent to prepare flat sheet and hollow fiber membranes using a liquid–liquid phase separation technique. The PVP block formed a brush on the surface of the blended membrane, while the PMMA block mingled with the PES macromolecules, which endowed the membrane with permanent hydrophilicity. After adding the as-prepared block co-polymer the modified membranes showed lower protein (bovine serum albumin) adsorption, suppressed platelet adhesion, and a prolonged blood coagulation time, and thereby the blood compatibility was improved. Furthermore, the modified PES membranes showed good cytocompatibility, ultrafiltration and protein anti-fouling properties. These results suggest that surface modification of PES membranes by blending with the amphiphilic triblock co-polymer PVP-b-PMMA-b-PVP allows practical application of these membranes with good biocompatibility in the field of blood purification, such as hemodialysis and bioartificial liver support.
Co-reporter:Qiang Wei;Beijia Li;Nan Yi;Baihai Su;Zehua Yin;Fulong Zhang;Jie Li
Journal of Biomedical Materials Research Part A 2011 Volume 96A( Issue 1) pp:38-45
Publication Date(Web):
DOI:10.1002/jbm.a.32956
Abstract
In this article, we presented a general protocol to prepare biomolecule-immobilized mussel-inspired polydopamine (PDA) coatings to improve the blood compatibility of broad ranges of material surfaces. It needs only a simple immersion of substrates in dopamine solution at alkaline pH to form mussel-inspired PDA coating, and then immersing the PDA coated substrates into biomolecule solution to conjugate biomolecules. XPS, water contact angle analysis, and protein assay confirmed that biomolecules could be successfully coated on several material surfaces, including nylon, cellulose, and polyethersulfone membrane surfaces. For the protein fouling resistance, the bovine serum albumin (BSA) modified surfaces were more effective than the amino acid modified surfaces. And the platelet adhesion on the BSA-modified material surfaces was obviously depressed. These results indicated that the blood compatibility of the surfaces was improved by the biomacromolecule-immobilized mussel-inspired coating which might be considered as a universal coating to modify a wide variety of materials. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Co-reporter:Weifeng Zhao, Chao He, Huiyuan Wang, Baihai Su, Shudong Sun, and Changsheng Zhao
Industrial & Engineering Chemistry Research 2011 Volume 50(Issue 6) pp:3295-3303
Publication Date(Web):February 7, 2011
DOI:10.1021/ie102251v
Well-defined block copolymers, poly(ethylene glycol) methyl ether-b-poly(styrene) (mPEG-b-PS), in which the PS blocks had different molecular weights, were synthesized by atom-transfer radical polymerization (ATRP) and characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC). The block copolymers were then used as amphiphilic additives to modify polyethersulfone (PES) hollow fiber membranes to improve the antifouling property. Static contact angle measurement indicated the increase of the membrane surface hydrophilicity, and scanning electron micrograph (SEM) suggested that the modified membranes preserved asymmetric structure. Protein ultrafiltration experiments showed that the antifouling ability of the modified membranes enhanced. After three cycles of BSA solution (1.0 mg/mL) ultrafiltration and three times of hydraulic cleaning, the water flux recovery ratios (FRR) of the mPEG-b-PS modified membranes were still as high as 85.6%. The hydrophilic modification with mPEG-b-PS copolymers is a good method to improve the antifouling property of PES hollow fiber membranes.
Co-reporter:Zehua Yin;Kaiyu Fu;Jian Gao;Xuelian Cao;Lulu Li
Journal of Applied Polymer Science 2011 Volume 119( Issue 6) pp:3607-3614
Publication Date(Web):
DOI:10.1002/app.33050
Abstract
In this article, a novel poly-(acrylic acid-acrylonitrile) (PAA-AN)/filter paper composite membrane with pH-sensitivity was developed. The membrane was composed of three layers. The top and bottom layers were made of PAA-AN copolymer, while the middle layer was filter paper. The filter paper was used to enhance the strength of the membrane. The PAA-AN/filter paper membrane showed evident pH sensitivity and pH reversibility as the pH value changed between 2.0 and 9.5. With the increase of the PAA-AN copolymer amount in the composite membrane, the pH sensitivity increased. The Cu (II) ion-exchange experiment indicated that the membrane could bind metal ions and could be used as ion-exchange membrane to purify water. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Co-reporter:Xue L. Cao;Chong Cheng;Ze H. Yin;Peng L. Bai;Qiang Wei;Bao H. Fang ;Chang S. Zhao
Journal of Applied Polymer Science 2011 Volume 120( Issue 1) pp:345-350
Publication Date(Web):
DOI:10.1002/app.33137
Abstract
A new method to introduce iminodiacetic acid (IDA) onto polyethersulfone (PES) matrix through chlorosulfonation was described in this work, and the prepared PES-IDA was used as adsorbent for the removal of metal ions from aqueous solutions. Chlorosulfonic groups (SO2Cl) were introduced onto PES first, then IDA was grafted onto PES by using the interactions between the chlorosulfonic group and the imino group of IDA. The grafted IDA was characterized by fourier transform infrared measurement, X-ray photoelectron spectroscopy analysis, and thermogravimetric analysis spectra. The adsorbed amounts by the PES-IDA for Cu2+ and Ag+ were 3.44 mg/g and 7.09 mg/g, respectively. The PES-IDA adsorbent may expand the usage of PES in purification fields and could make some potential contributions to the polymer-based adsorbents. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Co-reporter:Dongsheng Wang, Wen Zou, Lulu Li, Qiang Wei, Shudong Sun, Changsheng Zhao
Journal of Membrane Science 2011 374(1–2) pp: 93-101
Publication Date(Web):
DOI:10.1016/j.memsci.2011.03.021
Co-reporter:Chong Cheng, Lang Ma, Danfeng Wu, Jian Ren, Weifeng Zhao, Jimin Xue, Shudong Sun, Changsheng Zhao
Journal of Membrane Science 2011 378(1–2) pp: 369-381
Publication Date(Web):
DOI:10.1016/j.memsci.2011.05.028
Co-reporter:Lulu Li, Zehua Yin, Feilong Li, Tao Xiang, Yao Chen, Changsheng Zhao
Journal of Membrane Science 2010 Volume 349(1–2) pp:56-64
Publication Date(Web):1 March 2010
DOI:10.1016/j.memsci.2009.11.018
In this paper, functional terpolymers of poly(acrylonitrile-acrylic acid-vinyl pyrrolidone) (P (AN-AA-VP)) with different monomer proportion were synthesized via free radical solution polymerization using N-methyl-2-pyrrolidone (NMP) as the solvent. Fourier transform infrared (FTIR) analysis and differential scanning calorimetry (DSC) confirmed that the terpolymers were successfully synthesized. Elemental analysis data was used to calculate the molar ratio of acrylonitrile (AN), acrylic acid (AA) and vinyl-pyrrolidone (VP) in the random terpolymers. The molecular weights of the terpolymers were determined by gel permeation chromatography technique (GPC). The terpolymers were water insoluble due to the AN chains. The AA and VP chains were hydrophilic chains. Furthermore, the AA provided negative charge, while the VP provided the miscibility with polyethersulfone (PES), which was widely used as membrane material. Thus, the terpolymers can be directly blended with PES as a macromolecule additive using NMP as the solvent to prepare membranes. The water contact angles for the modified membranes decreased obviously; while the water flux significantly increased, and the membrane flux showed pH dependence; in addition, when the terpolymer was blended in the membrane, the protein adsorption decreased, while the protein anti-fouling property increased.
Co-reporter:Wen Zou, Yun Huang, Jie Luo, Jia Liu, Changsheng Zhao
Journal of Membrane Science 2010 Volume 358(1–2) pp:76-84
Publication Date(Web):15 August 2010
DOI:10.1016/j.memsci.2010.04.028
In this study, the functional terpolymer of poly (methyl methacrylate–acrylic acid–vinyl pyrrolidone) was synthesized via free radical solution polymerization using dimethylacetamide (DMAC) as the solvent. The terpolymer can be directly blended with polyethersulfone (PES) using DMAC as the solvent to prepare PES hollow fiber membrane by using a dry-wet spinning technique based on a liquid–liquid phase separation technique. The blended PES hollow fiber membranes showed evident pH sensitivity; and the pH-valve effect was observed at the pH values between 7.0 and 10.0. The fluxes under acid conditions were over 10 times larger than those under basic conditions, and with the increase of the terpolymer blended in the membranes, the flux change increased. The fluxes also showed pH reversibility. Both the pore size change and the electroviscous effect had great effect on the pH sensitivity. Furthermore, the hydrophilicity of the blended membranes increased, and the membranes showed good protein antifouling property.
Co-reporter:Qiang Wei, Fulong Zhang, Jie Li, Beijia Li and Changsheng Zhao
Polymer Chemistry 2010 vol. 1(Issue 9) pp:1430-1433
Publication Date(Web):07 Sep 2010
DOI:10.1039/C0PY00215A
Polydopamine-coatings can be prepared in acidic, neutral and alkaline aqueous media by oxidant-induced polymerization, which is material-independent and multifunctional for surface modification.
Co-reporter:Baohong Fang;Chong Cheng;Lulu Li;Jia Cheng;Weifeng Zhao
Fibers and Polymers 2010 Volume 11( Issue 7) pp:960-966
Publication Date(Web):2010 October
DOI:10.1007/s12221-010-0960-5
Poly (acrylonitrile-co-vinyl pyrrolidone-co-acrylic acid) (P(AN-VP-AA)) was synthesized via free radical copolymerization, and used to blend with polyethersulfone (PES) to prepare PES membrane, and followed by grafting bovine serum albumin (BSA) onto the surface of the membrane. Compared to binary copolymers, such as P(VP-AA) and P(ANAA), the blending amounts of the terpolymer and the BSA grafting amounts increased. To confirm the existence of BSA on the membrane surface, micro BCA™ protein assay, XPS and ATR-FTIR analysis were used. The water contact angle, protein adsorption and platelet adhesion were obviously decreased after grafting BSA onto the membrane surface. Furthermore, the antithrombogenicity of the modified membranes, such as the prothrombin time (PT) and activated partial thromboplastin time (APTT) increased, and the cytocompatibility increased. These results indicated that the BSA modified PES membranes had a good biocompatibility.
Co-reporter:X. L. Cao;C. Cheng;Y. L. Ma;C. S. Zhao
Journal of Materials Science: Materials in Medicine 2010 Volume 21( Issue 10) pp:2861-2868
Publication Date(Web):2010 October
DOI:10.1007/s10856-010-4133-2
Silver nanoparticles were prepared by chemical reduction method using chitosan as stabilizer and ascorbic acid as reducing agent in this work. The silver/chitosan nanocomposites were characterized in terms of their particle sizes and morphology by using UV spectrophotometer, nano-grainsize analyzer, and transmission electron microscopy. Antibacterial activities of these nanocomposites were carried out for Staphylococcus aureus and Escherichia coli. The silver nanoparticles exhibited significantly inhibition capacity towards these bacteria. Detailed studies on the biocompatibility of the silver/chitosan nanocomposites were investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and cell adhesion test. The results indicated that these silver/chitosan nanocomposites were benefit for the proliferation and adhesion of L-929 cells, and the biocompatibilities between the nanocomposites and the cells would become better with the culturing days. We anticipated that these silver/chitosan nanocomposites could be a promising candidate as coating material in biomedical engineering and food packing fields wherein antibacterial properties and biocompatibilities are crucial.
Co-reporter:Xuelian Cao, Ming Tang, Fei Liu, Yuanyang Nie, Changsheng Zhao
Colloids and Surfaces B: Biointerfaces 2010 Volume 81(Issue 2) pp:555-562
Publication Date(Web):1 December 2010
DOI:10.1016/j.colsurfb.2010.07.057
By using the interaction between the sulfonated groups and silver ions, silver nanoparticles were successfully introduced onto the surface of sulfonated polyethersulfone (SPES) membranes by using vitamin C as reducing agent. The presence of silver nanoparticles on the surface of the PES/SPES hybrid membranes was characterized by UV spectrophotometer, scanning electron microscopy and transmission electron microscopy. Detailed studies on the antibacterial activity of the (PES/SPES)-Ag composites were carried out for Staphylococcus aureus, Staphylococcus albus, and Escherichia coli, for which, the composites exhibited significantly inhibition capacity. Cytocompatibility of the (PES/SPES)-Ag composites were also investigated by cell cytotoxicity and cell adhesion tests. The results indicated that after immobilizing with silver nanoparticles, the (PES/SPES)-Ag was still within the safe use range. To our knowledge, this is the first time that PES membranes have been prepared with antibacterial capacity. We anticipate that this novel and green method might lead to an expanded usage of PES with antibacterial properties in medical instruments and food processing industries in the future, and might also make a potential contribution to the fields of antibacterial chemistry.
Co-reporter:Bosi Qian, Jie Li, Qiang Wei, Pengli Bai, Baohong Fang, Changsheng Zhao
Journal of Membrane Science 2009 Volume 344(1–2) pp:297-303
Publication Date(Web):15 November 2009
DOI:10.1016/j.memsci.2009.08.026
In this study, a simplified method to prepare pH-sensitive polyethersulfone (PES) hollow fiber membranes was provided by blending with a copolymer of acrylonitrile and acrylic acid (PANAA). The copolymer PANAA was synthesized by free radical solution polymerization using N-methyl pyrrolidone (NMP) as the solvent. The PANAA copolymer solution can be directly blended with PES solution (using NMP as the solvent) to prepare hollow fibers by using a dry–wet spinning technique based on the liquid–liquid phase separation technique. The blended PES hollow fiber membranes showed evident pH-sensitivity and pH reversibility; and the pH-valve effect was observed at the pH between 4.5 and 11.0. We also proved that the electroviscous effects played the most important role on the pH-sensitivity and flux control for the blended membranes.
Co-reporter:Qiang Wei, Jie Li, Bosi Qian, Baohong Fang, Changsheng Zhao
Journal of Membrane Science 2009 Volume 337(1–2) pp:266-273
Publication Date(Web):15 July 2009
DOI:10.1016/j.memsci.2009.03.055
In this paper, we provide a simplified method to prepare functional polyethersulfone (PES) membranes with pH sensitivity and ion-exchange capacity by blending cross-linked poly (acrylic acid) (PAA) sub-micrometer-scale gels. The PAA gels were synthesized through the solution polymerization of acrylic acids in dimethylacetamide (DMAC) under strong agitation, the size of the gels ranged from about 250 to 3000 nm. With the increase of the agitation rate, the gel size increased. The PAA gel solution can be directly blended with PES solution (using DMAC as the solvent) to prepare membrane using a phase separation technique. After blending the PAA gels, the morphology of the PES membrane was substantially altered; and the finger-like structure became a sponge-like structure. The blended PES membranes showed evident pH sensitivity and pH reversibility; and the pH-valve effect was observed at pH between 3 and 8. With the increase of the gel size, the pH sensitivity increased; and with the increase of the gel amount blended in the membrane, the water flux increased under acid conditions. The permeability results suggested that the flux of acidic amino acid solution was higher than basic amino acid solution. The Cu2+ ion-exchange experiment indicated that the membranes could bind metal ions, and had potential to be used as ion-exchange membranes.
Co-reporter:Baohong Fang, Qiyao Ling, Weifeng Zhao, Yunli Ma, Pengli Bai, Qiang Wei, Haifeng Li, Changsheng Zhao
Journal of Membrane Science 2009 Volume 329(1–2) pp:46-55
Publication Date(Web):5 March 2009
DOI:10.1016/j.memsci.2008.12.008
Polyethersulfone (PES) membrane was modified by blending with a copolymer of acrylonitrile (AN) and acrylic acid (AA), followed by grafting bovine serum albumin (BSA) onto the surface of the membrane. The PES and PAN-AA blending membranes were prepared through spin coating coupled with a liquid–liquid phase separation technique. The Micro BCA™ protein assay, XPS and FTIR/ATR analysis confirmed that BSA was successfully grafted onto the surface of the membranes. The pre-activated carboxyl groups of the copolymer and the amino groups of the protein contributed to the formation of BSA-PES membrane conjugates. The water contact angle, protein adsorption and platelet adhesion were obviously decreased after grafting BSA onto the membrane surface, meanwhile the water flux of the membrane was significantly increased. All these results indicated that the hydrophilicity and blood compatibility of the modified PES membranes were improved.
Co-reporter:Xian Wen, Xuelian Cao, Zehua Yin, Ting Wang, Changsheng Zhao
Carbohydrate Polymers 2009 Volume 78(Issue 2) pp:193-198
Publication Date(Web):5 September 2009
DOI:10.1016/j.carbpol.2009.04.001
In this paper, we reported the synthesis and properties of interpenetrating polymer network (IPN) hydrogel systems designed for colon targeted drug delivery. The gels were composed of konjac glucomannan (KGM) and cross-linked poly(acrylic acid) (PAA) by N,N-methylene-bis-(acrylamide) (MBAAm). It was possible to modulate the swelling degree of the gels. And the swelling ratio has sensitive respondence to the environmental pH value variation. The degradation tests show that the hydrogels retain the enzymatic degradation character of KGM. In vitro release of model drug VB12 was studied in the presence of Cellulase E0240 in pH 7.4 phosphate buffer at 37 °C. The accumulative release percent of the model drug reached 85.6% after 48 h and the drug release was controlled by the swelling and the degradation of the hydrogels. The results indicated that the IPN hydrogels can be exploited as potential carriers for colon-specific drug delivery.
Co-reporter:W. F. Zhao;B. H. Fang;N. Li;S. Q. Nie;Q. Wei ;C. S. Zhao
Journal of Applied Polymer Science 2009 Volume 113( Issue 2) pp:916-921
Publication Date(Web):
DOI:10.1002/app.30014
Abstract
pH-responsive molecularly imprinted particles were successfully fabricated by pore-filling poly (acrylic acid) (PAA) gels into bisphenol-A (BPA)-imprinted polyethersulfone particles. The adsorbed BPA amount (or rate) decreased after filling the PAA gels both for the imprinted and nonimprinted particles. However, it was confirmed that changing the acidity of the solution reversibly controls the rebinding ability toward BPA and that the BPA uptake of the pore-filled particles exhibited chemical valve behavior at a pH between 3 and 6. This finding can be attributed to the swelling of the PAA gels in the particles. The present methodology provides a simple way to prepare pH-responsive molecularly imprinted materials and is expandable to the imprinting of other hydrophobic molecules, such as dibenzofuran. Also, the results of this work demonstrate the potential of stimuli-responsive molecularly imprinted polymer materials as smart chemicals and as drug-delivery systems. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Co-reporter:Yijia Zhang;Qiang Wei;Chuanbin Yi;Changyu Hu;WeiFeng Zhao
Journal of Applied Polymer Science 2009 Volume 111( Issue 2) pp:651-657
Publication Date(Web):
DOI:10.1002/app.29122
Abstract
In this study, polyethersulfone (PES)–alginate microcapsules were prepared for drug-controlled release, and vitamin B12 (VB12), rifampicin (RFP), and bovine serum albumin (BSA) were used as model drugs. Different microcapsules were prepared by the variation of the crosslinking degree of alginate and the variation of the chemical components of the microcapsule membrane, including the PES and polyethylene glycol (PEG) contents. Systematic experiments were carried out to study their influences on the release profile of the model drugs. The results showed that with the increase of the crosslinking degree of the alginate, the drug release rate increased; whereas with the increase of the PES concentration used to prepare the microcapsule membrane, the drug release rate decreased. The contents of the PEG in the microcapsule membrane also affected the drug release. This study enriched the methodology of the fabrication of the microcapsules, and the microcapsules may have a potential use for controlled release. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Co-reporter:Xingyi Xie;Ruifang Wang;Jiehua Li;Liang Luo;Da Wen;Yinping Zhong
Journal of Biomedical Materials Research Part B: Applied Biomaterials 2009 Volume 89B( Issue 1) pp:223-241
Publication Date(Web):
DOI:10.1002/jbm.b.31212
Abstract
Previous work has shown the synthesis of fluorocarbon chain (CF3(CF2)6CH2O-) end-capped poly(carbonate urethane)s (FPCUs) and confirmed the presence of a novel bilayered surface structure in FPCUs, that is, the top fluorocarbon and subsurface hard segment layers (Xie et al., J Biomed Mater Res Part A 2008; 84:30–43). In this work, the effects of such surface structure on blood compatibility were investigated using hemolytic test and platelet adhesion analysis. The chemical stability of the polymers was also determined by Zhao's glass wool-H2O2/CoCl2 test and phosphate-buffered saline (PBS, pH = 3.1–3.3) treatment. One of the FPCUs, FPCU-A, and two control materials, a poly(ether urethane) (PEU) and a poly(carbonate urethane) (PCU), were investigated. No significant difference in hemolytic indices was observed among the three materials, whereas the adherent density and deformation of platelets were much lower on FPCU-A compared with on PCU and PEU. Severe surface cracking and surface buckling developed in prestressed PEU and PCU films after H2O2/CoCl2 treatment, respectively, whereas smooth surface was observed for the FPCU-A. PBS incubation resulted in parallel ridge-like morphology in PCU whereas PEU and FPCU-A retained their smooth surfaces. Under relatively high stress conditions, all the materials developed well-oriented strip-like surface patterns. Results from ATR-FTIR spectra revealed a surface oxidation mechanism as described in literature. However, observations of universal decrease of molecular weights under stress conditions further suggested the presence of another bulk stress oxidation mechanism. Regardless the degradation mechanisms involved, the unique bilayered surface structure really improved the blood compatibility and chemical stability of FPCU-A, indicating that further in vivo investigations are worthwhile. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Co-reporter:Binyu Yu;Xinlan Zhang;Jie He;Kaiguang Yang
Journal of Applied Polymer Science 2008 Volume 108( Issue 6) pp:3859-3866
Publication Date(Web):
DOI:10.1002/app.28041
Abstract
In this study, molecular imprinted polyethersulfone (PES) particles were prepared by phase inversion technique. Bisphenol A, 4,4′-biphenol, and phenol were used as the template molecules, and the functional binding performance in aqueous medium towards the template molecules was investigated. The nonsolvent additives such as ethanol, water, chloroform, and toluene had no effect on the recognition property of the PES particles. The resultant BPA imprinted particles showed the highest BPA recognition coefficient, which was 2.14 times higher than that for the nonimprinted ones. The 4,4′-biphenol imprinted particles showed the highest binding ability towards the template which was 28.4 μmol/g. Scatchard analysis showed that there were two classes of binding sites formed in the imprinted particles, and the equilibrium dissociation constant of the highest affinity binding sites was estimated to be 9.2 μM. Finally, the interaction between PES and the templates was studied by Fourier transform infrared (FTIR) and NMR. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Co-reporter:Man Zhang, Rui Wang, Tao Xiang, Wei-Feng Zhao, Chang-Sheng Zhao
Journal of Industrial and Engineering Chemistry (25 February 2016) Volume 34() pp:415-421
Publication Date(Web):25 February 2016
DOI:10.1016/j.jiec.2015.12.016
•The poly(sodium p-styrenesulfonate)/poly(methyl methacrylate) particles were prepared by liquid–liquid phase separation technology.•The particles exhibited high adsorption ability for methylene blue and methyl violet.•The particles could be facilely fabricated and be industrially used for wastewater treatment.In this study, poly(sodium p-styrenesulfonate)/poly(methyl methacrylate) particles were facilely prepared by in situ cross-linked polymerization followed with a liquid–liquid phase inversion technique. The particles exhibited selective adsorption for cationic dyes due to the negatively charged sulfonic groups. The intra-particle diffusion process was the rate-limiting step for the adsorption of methylene blue. More than 90% of cationic dye was removed by the adsorption column of the particles after three circulations. The particles could be facilely fabricated and industrially used for wastewater treatment.Download high-res image (202KB)Download full-size image
Co-reporter:Zhiyuan Han, Chong Cheng, Lisha Zhang, Chongdan Luo, Chuanxiong Nie, Jie Deng, Tao Xiang, Changsheng Zhao
Desalination (15 September 2014) Volume 349() pp:80-93
Publication Date(Web):15 September 2014
DOI:10.1016/j.desal.2014.06.025
•Composite PES membrane was prepared via one-pot in-situ cross-linked copolymerization.•The composite membrane showed robust pH-responsive property.•The composite membrane exhibited excellent antifouling property.This study reports a novel and systematic strategy on the preparation and characterization of pH-responsive and anti-fouling composite membranes via one-pot in-situ cross-linked copolymerization. Typical commercial polyethersulfone (PES) is used as membrane matrix; poly (methyl methacrylate-co-acrylic acid) (P(MMA-AA)) and poly(methyl methylacrylate-co-4vinyl pyridine) (P(MMA-4VPy)) are applied as model pH-responsive copolymers. The casting solutions are directly synthesized by one-pot in-situ cross-linked copolymerization of MMA, AA/4VPy and cross-linker in PES solutions; then, composite membranes are obtained by a liquid–liquid phase inversion method. ATR-FTIR, water contact angle, membrane morphology, pH sensitivity and reversibility, protein anti-fouling property, and Cu2 + adsorption capacity for the composite membranes are systematically investigated. The cross-section SEM data indicated that the composite membranes owned typical finger-like structure; while the surface SEM images indicated that the in-situ copolymerized system exhibited excellent miscibility between PES and copolymers. The pH-responsive tests proved that the PES/P(MMA-AA) and PES/P(MMA-4VPy) membranes owned remarkable and reversible pH-responsive performance. Protein ultrafiltration experiments showed that the composite membranes exhibited excellent anti-fouling property. Furthermore, the prepared composite membranes exhibited good Cu2 + adsorption capacity. The results demonstrated that the proposed in-situ cross-linked copolymerization provided a facile and practical approach to fabricate pH-responsive and anti-fouling membranes for various applications.Download full-size image
Co-reporter:Man Zhang, Rui Wang, Zhenqiang Shi, Xuelian Huang, Weifeng Zhao, Changsheng Zhao
Journal of Hazardous Materials (15 January 2017) Volume 322(Part B) pp:499-507
Publication Date(Web):15 January 2017
DOI:10.1016/j.jhazmat.2016.10.016
•H-bonding and dipole-dipole interactions reinforced hydrogels are prepared.•Acrylonitrile based multi-responsive hydrogels are sol-gel reversible.•The hydrogels can be re-used for environmental pollution remediation.A novel family of multi-responsive, tough, and reversible hydrogels were prepared by the combination of dipole-dipole interaction, hydrogen bonding interaction and slightly chemical cross-linking, using monomers of acrylonitrile, sodium allylsulfonate and itaconic acid. Reversible gel-sol transition was achieved by the flexible conversion of the dipole-dipole interactions between acrylonitrile-acrylonitrile and acrylonitrile-sodium thiocyanate, and the hydrogels could freely form desired shapes. The dipole-dipole and hydrogen bonding interactions improved the mechanical strength of the hydrogels with a compressive stress of 2.38 MPa. Meanwhile, the hydrogels sustained cyclic compressive tests with 60% strain, and exhibited excellent elastic property. The hydrogels were sensitive to pH and ionic strength, and could keep their perfect spherical structures without any obvious cracks even after immersing in strong ionic strength (or pH) solution for several reversible cycles. Furthermore, the hydrogels were recycled for environmental pollution remediation, and showed great potential to be applied in water treatments and other related fields.Download full-size image
Co-reporter:Lingren Wang, Baihai Su, Chong Cheng, Lang Ma, Shuangsi Li, Shengqiang Nie and Changsheng Zhao
Journal of Materials Chemistry A 2015 - vol. 3(Issue 7) pp:NaN1404-1404
Publication Date(Web):2014/12/18
DOI:10.1039/C4TB01865F
In this study, to approach the scalable fabrication of super-hemocompatible and antibacterial membranes, surface engineered 3D heparin-mimicking coatings were designed by layer by layer (LBL) assembly of water-soluble heparin-mimicking polymer (WHP) and quaternized chitosan (QC). The low cost and scalable WHP was synthesized by a combination of polycondensation and post-carboxylation method, and the antibacterial QC was prepared by a two-step quaternization reaction. Then, the as-prepared negatively charged WHP and positively charged QC were used to conduct the LBL assembly on the widely used poly(ether sulfone) (PES) membrane surface to prepare heparin-mimicking modified membrane. The results indicated that the assembled heparin-mimicking coating nanofilms exhibited 3D porous morphology. The systematic blood compatibility and antithrombotic evaluation revealed that the functionalized membrane owned prolonged clotting times and greatly suppressed platelet adhesion and activation; further contacting activation detection (TAT and PF-4) and complement activation (C3a and C5a) experiments indicated that the heparin-mimicking membranes had lower blood activation compared to the pristine membrane. The cell observations demonstrated that the surface assembled heparin-mimicking nanofilms showed superior performances in endothelial cells adhesion and growth than the pure PES membrane. The results of the antibacterial study indicated that the QC contained coating exhibited significant inhibition ability for both Escherichia coli and Staphlococcus aureus. In general, the LBL assembled heparin-mimicking coatings conferred the functionalized PES membranes with integrated blood compatibility, cytocompatibility and antibacterial property for multi-applications, which may forward the fabrication and application of heparin-mimicking biomedical devices.
Co-reporter:Yi Xia, Chong Cheng, Rui Wang, Chuanxiong Nie, Jie Deng and Changsheng Zhao
Journal of Materials Chemistry A 2015 - vol. 3(Issue 48) pp:NaN9304-9304
Publication Date(Web):2015/11/09
DOI:10.1039/C5TB01523E
A highly efficient, universal and convenient protocol is reported to fabricate antifouling, hemocompatible, and bactericidal membranes by physically blending antifouling nanogels and in situ silver nanoparticle immobilization. Firstly, nanogels are synthesized by one-step cross-linking co-polymerization of an antifouling monomer, poly(ethylene glycol) methacrylate (PEGMA), and an anchoring monomer, methylacrylic acid (MAA). Then, the nanogels are physically blended with a membrane matrix to generate nanogel embedded composite membranes. Finally, the in situ growth of silver nanoparticles in the composite membranes is successfully achieved by electrostatic adsorption of Ag+ ions and vitamin C reduction. The successful preparation of Ag-nanogel blended polymeric membranes has been confirmed by FTIR spectra and XPS patterns. The surface SEM images suggest that there are abundant Ag-nanogels embedded on the composite membrane surfaces. The cross-sectional SEM images give clear evidence that the Ag-nanogel immobilized composite membranes have well-maintained finger-like structure with increased porosity; meanwhile, the uniform distribution of the Ag-nanogels in the membrane matrix is confirmed by elemental EDX mapping. The systematic tests of water contact angle, static protein adsorption and ultrafiltration experiments indicate that the hydrophilicity, water flux, and antifouling properties of the composite membranes are substantially improved. More importantly, prolonged blood clotting time and suppressed platelet adhesion/activation indicate that the composite membranes have better blood compatibility and ultralow thrombotic potential. Bactericidal studies reveal that the modified membranes exhibit remarkable inhibition and killing capability toward both S. aureus and E. coli bacteria. The results reveal that robust antifouling, hemocompatible, and bactericidal composite membranes have been prepared via the proposed blending of nanogels and loading of Ag nanoparticles. This approach is believed to have great potential for fabricating various multifunctional membranes for industrial and clinical usage.
Co-reporter:Zihang Peng, Ye Yang, Jiyue Luo, Chuanxiong Nie, Lang Ma, Chong Cheng and Changsheng Zhao
Biomaterials Science (2013-Present) 2016 - vol. 4(Issue 9) pp:NaN1401-1401
Publication Date(Web):2016/08/02
DOI:10.1039/C6BM00328A
Polymer based hemoperfusion has been developed as an effective therapy to remove the extra bilirubin from patients. However, the currently applied materials suffer from either low removal efficiency or poor blood compatibility. In this study, we report the development of a new class of nanofibrous absorbent that exhibited high bilirubin removal efficiency and good blood compatibility. The Kevlar nanofiber was prepared by dissolving micron-sized Kevlar fiber in proper solvent, and the beads were prepared by dropping Kevlar nanofiber solutions into ethanol. Owing to the nanofiborous structure of the Kevlar nanofiber, the beads displayed porous structures and large specific areas, which would facilitate the adsorption of toxins. In the adsorption test, it was noticed that the beads possessed an adsorption capacity higher than 40 mg g−1 towards bilirubin. In plasma mimetic solutions, the beads still showed high bilirubin removal efficiency. Furthermore, after incorporating with carbon nanotubes, the beads were found to have increased adsorption capacity for human degradation waste. Moreover, the beads showed excellent blood compatibility in terms of a low hemolysis ratio, prolonged clotting times, suppressed coagulant activation, limited platelet activation, and inhibited blood related inflammatory activation. Additionally, the beads showed good compatibility with endothelial cells. In general, the Kevlar nanofiber beads, which integrated with high adsorption capacity, good blood compatibility and low cytotoxicity, may have great potential for hemoperfusion and some other applications in biomedical fields.
Co-reporter:Chong Cheng, Shudong Sun and Changsheng Zhao
Journal of Materials Chemistry A 2014 - vol. 2(Issue 44) pp:NaN7672-7672
Publication Date(Web):2014/09/12
DOI:10.1039/C4TB01390E
Research into the design of heparin and heparin-like/mimicking polymer-functionalized biomedical membranes is of tremendous interest to the biomedical sector in particular and is driven by potential diverse biomedical applications such as blood purification, artificial organs and other clinical medical devices. In this review, we highlight the progress of the recent research and propose potential biomedical applications in the fields of surface heparinization and the heparin-inspired modification of polymeric membranes. We summarize various surface heparinization strategies such as blending, surface coating, grafting, layer-by-layer assembly and mussel-inspired coating. Then, we classify the heparin-like/mimicking polymers and their applications in the design of heparin-mimicking biomedical membranes and draw some conclusions. The general concept of heparin-like/mimicking polymers is usually defined as heparan sulfates or synthetic sulfated/carboxylated polymers with comparable biologically mimicking functionalities as heparin, especially anticoagulant activity. Moreover, the potential biomedical applications and benefits of heparin and heparin-like/mimicking polymer-functionalized membranes in blood purification, artificial organs and tissue engineering are also discussed in each section. The heparin and heparin-like/mimicking polymer-functionalized membranes presented are exceptional candidates for the treatment of organ failure and many other blood-contacting fields. Finally, we conclude with the challenges and future perspectives for the strategies toward the heparinization and heparin-like/mimicking modification of membrane surfaces. It is believed that this review will evoke more attention towards the design of heparinized and heparin-like/mimicking membranes and encourage future advancements of this emerging research field.
Co-reporter:Lang Ma, Hui Qin, Chong Cheng, Yi Xia, Chao He, Chuanxiong Nie, Lingren Wang and Changsheng Zhao
Journal of Materials Chemistry A 2014 - vol. 2(Issue 4) pp:NaN375-375
Publication Date(Web):2013/11/08
DOI:10.1039/C3TB21388A
In this study, multifunctional mussel-inspired self-coated membranes with remarkable blood and cell compatibilities are prepared by a facile and green approach. A highly sulfonated linear heparin-like polymer (HepLP, poly(sodium 4-vinylbenzenesulfonate)-co-poly(sodium methacrylate)) and heparin are chosen for the mussel-inspired heparin-mimicking coating, respectively. Firstly, DA is grafted onto the backbone of HepLP or heparin to obtain DA grafted HepLP (DA-g-HepLP) or DA grafted heparin (DA-g-Hep) by means of the carbodiimide chemistry method. Then, the DA-g-HepLP and DA-g-Hep are used to prepare surface coated heparin-mimicking substrates; the polyethersulfone (PES) dialysis membrane is chosen as the model substrate. The coated surface composition, surface morphology, water contact angle, surface zeta-potential, blood compatibility and cell compatibility are systematically investigated. The results of surface spectra, scanning electron microscopy (SEM) and atomic force microscopy (AFM) indicated that the DA-g-HepLP and DA-g-Hep were successfully coated onto the membranes. The coated membranes showed increased hydrophilicity and electronegativity, decreased plasma protein adsorption, and suppressed platelet adhesion compared to the pristine membrane. The cell morphology observation and cytotoxicity assays demonstrated that the surface coated heparin-mimicking membranes showed superior performance in endothelial cell proliferation and morphology differentiation. In addition, the excellent anticoagulant bioactivities indicated that the adhered DA-g-HepLP (or DA-g-Hep) could function or maintain its biological activity after the immobilization. In general, the mussel-inspired protocol of surface self-coating conferred the modified membranes with integrated blood compatibility, cell proliferation and biological activity for multi-biomedical applications, like hemodialysis, blood purification, organ implantation, and cell and tissue cultures.
Co-reporter:Fen Ran, Xiaoqin Niu, Haiming Song, Chong (Sage) Cheng, Weifeng Zhao, Shengqiang Nie, Lingren Wang, Aimei Yang, Shudong Sun and Changsheng Zhao
Biomaterials Science (2013-Present) 2014 - vol. 2(Issue 4) pp:NaN547-547
Publication Date(Web):2014/01/08
DOI:10.1039/C3BM60250H
Comb-like amphiphilic copolymers (CLACs) consisting of functional chains of poly(vinyl pyrrolidone) and polyethersulfone-based hydrophobic chains were firstly synthesized by reversible addition–fragmentation chain transfer polymerization. The CLAC can be used as an additive to blend with polyethersulfone (PES) at any ratio due to the excellent miscibility, and then a surface segregation layer with permanent hydrophilicity could be obtained. The surfaces of the CLAC modified PES membranes were characterized using X-ray photoelectron spectroscopic analysis, Fourier transform infrared and water contact angle measurements. The surfaces are self-assembled with numerous functional branch-like –PVP chains, which can improve the hemocompatibility. The root-like –PES chains (the hydrophobic part) are embedded in the membranes firmly, which greatly reduces the elution during the membrane preparation procedure and repeated usage, and makes the membranes have a permanent stability. The PES-based hydrophobic chains have the same structure as the membrane bulk material, which makes the miscibility of the additive and the membrane material good to ensure the intrinsic properties of the membrane. The modified membranes showed suppressed platelet adhesion and prolonged blood coagulation time (activated partial thromboplastin time, APTT); thus, the blood compatibility of the membranes was highly improved. The strategy may be extended to synthesize other PES-based functional copolymers and to prepare a modified PES dialysis membrane for blood purification.
Co-reporter:Shengqiang Nie, Min Tang, Chong (Sage) Cheng, Zehua Yin, Lingren Wang, Shudong Sun and Changsheng Zhao
Biomaterials Science (2013-Present) 2014 - vol. 2(Issue 1) pp:NaN109-109
Publication Date(Web):2013/09/17
DOI:10.1039/C3BM60165J
In the present work, inspired by the chemical structure of heparin molecules, we designed a polyethersulfone (PES) membrane with a heparin-like surface for the first time by physically blending sulfonated polyethersulfone (SPES), carboxylic polyethersulfone (CPES), and PES at rational ratios. Evaporation and phase-inversion membranes of PES/CPES/SPES were prepared by evaporating the solvent in a vacuum oven, and by a liquid–liquid phase separation technique, respectively. Scanning electron microscopy (SEM) images revealed that the structures of the PES/CPES/SPES membranes were dependent on the proportions of the additives and no obvious phase separation was detected. The blood compatibility of the modified membrane surfaces was characterized in terms of bovine serum fibrinogen (BFG) adsorption, platelet adhesion, thrombin–antithrombin (TAT) generation, percentage of platelets positive for CD62p expression, clotting times (activated partial thromboplastin time (APTT) and prothrombin time (PT)), and complement activation on C3a and C5a levels. The results indicated that the blood compatibility of PES matrix was improved due to the biologically inspired membrane design with a heparin-like interface by introducing functional sulfonic acid and carboxylic acid groups. Furthermore, cell morphology observation and cell culture assays demonstrated that the modified membranes showed better performance in bio-artificial liver related cell proliferation than the pristine PES membrane. In general, the intriguing PES/CPES/SPES membranes, especially the phase-inversion one, showed improved blood and cell compatibility, which might have great potential application in the blood purification field.
Co-reporter:Chao He, Zhen-Qiang Shi, Lang Ma, Chong Cheng, Chuan-Xiong Nie, Mi Zhou and Chang-Sheng Zhao
Journal of Materials Chemistry A 2015 - vol. 3(Issue 4) pp:NaN602-602
Publication Date(Web):2014/11/11
DOI:10.1039/C4TB01806K
Studies on the design of heparin and heparin-mimicking polymer based hydrogels are of tremendous interest and are fuelled by diverse emerging biomedical applications, such as antithrombogenic materials, growth factor carriers, and scaffolds for tissue engineering and regeneration medicine. In this study, inspired by the recent developments of heparin-based hydrogels, graphene oxide (GO) based heparin-mimicking hydrogels with hemocompatibility and versatile properties were prepared via free radical copolymerization, and poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 2-hydroxyethyl methacrylate (HEMA) hydrogels were used as the control samples. The GO based heparin-mimicking polymeric hydrogels exhibited interconnected structures with thin pore walls and high porosity. Because of the increased ionization and electrostatic repulsion of sodium styrene sulfonate (SSNa) segments, the swelling ratios of the SSNa added hydrogels were dramatically increased; after incorporating flexible GO nanosheets, as the 3D skeleton of the hydrogels, the swelling ability was further increased. In addition, the GO based heparin-mimicking hydrogels showed superior red blood cell compatibility, anti-platelet adhesion ability and anticoagulant ability. Furthermore, drug release data indicated that the GO based heparin-mimicking hydrogels had high drug loading ability and prolonged drug releasing ability; the antibacterial tests showed coincident results with large inhibition zones and long effective periods. Due to the integration of blood compatibility, drug loading and releasing abilities, as well as an excellent ability for the removal of toxic molecules, the GO based heparin-mimicking hydrogels can be used for versatile biomedical applications.
Co-reporter:Lang Ma, Chong Cheng, Chuanxiong Nie, Chao He, Jie Deng, Lingren Wang, Yi Xia and Changsheng Zhao
Journal of Materials Chemistry A 2016 - vol. 4(Issue 19) pp:NaN3215-3215
Publication Date(Web):2016/03/22
DOI:10.1039/C6TB00636A
In this work, we synthesized novel sodium alginate sulfates (SASs) with different sulfation degrees, which had similar chemical structure and bioactivity as those of heparin. Blood clotting time tests indicated that the heparin-mimetic SASs exhibited excellent and sulfation-degree-dependent anticoagulant activity. Beyond applications as anticoagulant reagents, the heparin-mimetics also showed potential applications for surface modification of blood-contacting devices. To achieve the goal of surface modification, we synthesized the mussel inspired adhesive macromolecules, dopamine grafted SASs (DA-g-SASs), which were capable of coating the surface of polymeric substrates in a basic buffer solution in a substrate-independent manner. The DA-g-SASs exhibited substrate-independent adhesive affinity to a variety of solid surfaces due to the formation of irreversible covalent bonds. By using polyethersulfone (PES) as a model blood contacting substrate, the surface properties of DA-g-SASs coated substrates were fully explored. ATR-FTIR and XPS spectra demonstrated the successful formation of the heparin-mimetic coatings. Endothelial cell staining and morphological observations revealed that the heparin-mimetic coatings could significantly promote cell adhesion and proliferation. In addition, systematic in vitro studies of blood clotting, protein adsorption, platelet adhesion, and blood-related complement activation demonstrated that the heparin-mimetic macromolecule coated substrates dramatically inhibited the thrombotic potential and inflammation induced by the material interface. Combining the above advantages, it is believed that the proposed integration of heparin-mimetic SASs and mussel inspired coating may open new operational principles for surface anticoagulant modification of various biological and clinical devices for blood purification, tissue implants, and other micro-nanoscale materials.
Co-reporter:Chong Cheng, Shengqiang Nie, Shuang Li, Hong Peng, Hang Yang, Lang Ma, Shudong Sun and Changsheng Zhao
Journal of Materials Chemistry A 2013 - vol. 1(Issue 3) pp:NaN275-275
Publication Date(Web):2012/09/19
DOI:10.1039/C2TB00025C
A green and facile method for preparing biopolymer functionalized reduced graphene oxide (RGO) by using mussel inspired dopamine (DA) as the reducing reagent and the functionalized molecule is proposed. In the study, GO is reduced by DA and DA is adhered to RGO by one-step pH-induced polymerization of DA (polydopamine, PDA), and then heparin or protein is grafted onto the PDA adhered RGO (pRGO) through catechol chemistry. The obtained pRGO, heparin grafted pRGO (Hep-g-pRGO), and BSA grafted pRGO (BSA-g-pRGO) exhibit fine 2D morphology and excellent stability in water and PBS solution. Furthermore, the biocompatibility of the biopolymer functionalized RGO are investigated using human blood cells and human umbilical vein endothelial cells (HUVECs). The biopolymer functionalized RGO exhibits an ultralow hemolysis ratio (lower than 1.8%), and the cellular toxicity assay suggests that the biopolymer functionalized RGO has good cytocompatibility for HUVEC cells, even at a high concentration of 100 μg mL−1. Moreover, the high anticoagulant ability of Hep-g-pRGO indicates that the grafted biopolymer could maintain its biological activity after immobilization onto the surface of pRGO. Therefore, the proposed safe and green biomimetic method confers the biopolymer functionalized RGO with great potential for various biological and biomedical applications.
Co-reporter:Jie Deng, Xinyue Liu, Lang Ma, Chong Cheng, Shudong Sun and Changsheng Zhao
Journal of Materials Chemistry A 2016 - vol. 4(Issue 4) pp:NaN703-703
Publication Date(Web):2015/12/17
DOI:10.1039/C5TB02072G
The development of biointerfaces with switchable properties is of growing interest for fabricating advanced biomaterials since the adjustment of surface properties can be made on demand. Herein, we report a highly versatile approach for the preparation of a switchable biointerface through a dynamic covalent bond (DCB). The switchability can be achieved via the reversible attaching/detaching of aldehyde end-functionalized biomacromolecules onto/from an acylhydrazide anchored substrate surface. By applying the DCB protocol, three types of well-designed aldehyde end-functionalized biomacromolecules including aldehyde-poly(styrenesulfonate)-co-poly(ethylene glycol)methyl ether methacrylate (Ald-PSP, blood compatible), aldehyde-poly([2-(meth acryloyloxy)ethyl]trimethylammonium chloride) (Ald-PMT, antibacterial), and aldehyde-poly([2-(meth acryloyloxy)ethyl]trimethylammonium chloride-co-poly(ethylene glycol)methyl ether methacrylate) (Ald-PMP, combined antifouling and antibacterial) could be reversibly and alterably immobilized on the substrate surface by switching the pH conditions. As a result, we succeeded in altering the biointerface performances; excellent blood compatibility, antibacterial ability, or combined antifouling and antibacterial capabilities could be alterably achieved on the biointerface, which made the obtained material interfaces more adaptable and capable of satisfying different biofunctional requirements. Moreover, many other properties with specific biofunctions of interests can also be achieved via designing specific aldehyde-terminated molecules.
Co-reporter:Chuanxiong Nie, Chong Cheng, Zihang Peng, Lang Ma, Chao He, Yi Xia and Changsheng Zhao
Journal of Materials Chemistry A 2016 - vol. 4(Issue 16) pp:NaN2756-2756
Publication Date(Web):2016/03/08
DOI:10.1039/C6TB00470A
Silver nanoparticle (AgNP)-based nanohybrids have been proposed as efficient antimicrobial agents because of their robust bactericidal activity. However, the direct exposure of AgNPs poses a threat towards mammalian cells. In this article, we report a facile mussel-inspired approach to introduce functional biopolymer coatings to shield AgNP-loaded oxidized carbon nanotubes (AgNPs@oCNT), as well as to modify the interface properties. Two kinds of dopamine-grafted functional biopolymers, heparin and chitosan, were used to reduce the Ag+ ions pre-absorbed onto the oCNT surface and simultaneously form protective coating layers. Their effects on the bactericidal activity and mammal cell biocompatibility of the AgNPs@oCNT were compared. The TEM, FTIR, and XPS results clearly verified the loading of AgNPs and the coating of functional biopolymer on the oCNT surface. Studies of broth turbidity, bacterial growth kinetics, agar plate counts, and live/dead bacterial staining revealed that the biopolymer-coated nanohybrids exhibited robust bactericidal activity against both Gram negative and Gram positive bacteria, and were as effective as bare AgNPs@oCNT hybrids. The chitosan-coated samples were particularly effective because of the synergistic effects of chitosan and AgNPs. The shielding effects of the anchored functional biopolymers gave the AgNP-based nanohybrids good compatibility with endothelial cells, especially for the heparin-coated samples.
Co-reporter:Chong Cheng, Ai He, Chuanxiong Nie, Yi Xia, Chao He, Lang Ma and Changsheng Zhao
Journal of Materials Chemistry A 2015 - vol. 3(Issue 20) pp:NaN4180-4180
Publication Date(Web):2015/04/15
DOI:10.1039/C5TB00136F
This study reports a highly efficient, convenient and universal protocol for the fabrication of robust antifouling and antibacterial polymeric membranes via one-pot cross-linked copolymerization of methyl acryloyloxygen ethyl trimethyl ammonium chloride (DMC) and poly(ethylene glycol) methyl ether methacrylate (PEGMA). The infrared testing and X-ray photoelectron spectroscopy gave obvious evidence that abundant DMC and PEGMA chains had enriched on the membrane surface. The surface and cross-sectional SEM images indicated that the addition of DMC and PEGMA had a little effect on the membrane roughness and inner structure. Meanwhile, the systematic investigations into the water contact angle, protein adsorption, ultrafiltration and bacterial inhibition indicated that the composite membranes showed improved hydrophilicity, decreased protein adsorption, increased water flux and antifouling property, as well as greatly enhanced antibacterial ability. Furthermore, it was found that the cross-linked copolymerization could further endow the composite membrane with multi-chemical properties, for instance the charged interface. As a model system, Ag nanoparticle-PDMC multilayers were coated onto the positively charged PES–DMC6 membranes via layer by layer assembly, and the successful surface coating confirmed their versatile ability and also provided a more effective and durable antibacterial coating to the composite membranes. All these results suggest that the robust antifouling and antibacterial composite membranes can be prepared via the proposed one-pot cross-linked copolymerization, and it is believed that this approach has great potential to be applied in various biomedical or industrial fields where antifouling and antibacterial properties are highly demanded.
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