Co-reporter:Jiayuan He;Shilang Gui;Yanyan Huang;Fang Hu;Yulong Jin;Yang Yu;Guanxin Zhang;Deqing Zhang
Chemical Communications 2017 vol. 53(Issue 80) pp:11091-11094
Publication Date(Web):2017/10/05
DOI:10.1039/C7CC06485C
A fast and sensitive method was established for an in-solution selection of cancer cell-targeting peptides at “single-residue resolution” by using the switchable fluorescence of tetraphenylethylene. The selected peptides have potential for biomarker tracing and can be used for targeted delivery of different cargos into living cancer cells.
Co-reporter:Yang Yu, Yanyan Huang, Yulong Jin, Rui Zhao
Biosensors and Bioelectronics 2017 Volume 94(Volume 94) pp:
Publication Date(Web):15 August 2017
DOI:10.1016/j.bios.2017.03.067
•Peptides were screened with SPRi and fluoroimmuno assays for the binding with HSA.•A hetero bivalent peptide with nM-level affinity to HSA was identified.•The hetero dimer can sense the small structural difference between HSA and BSA.•The hetero dimer inhibited the binding between HSA and its antibody (IC50 83 nM).Peptide-protein interactions mediate numerous biologic processes and provide great opportunity for developing peptide probes and analytical approaches for detecting and interfering with recognition events. Molecular interactions usually take place on the heterogeneous surface of proteins, and the spatial distribution and arrangement of probes are therefore crucial for achieving high specificity and sensitivity in the bioassays. In this study, small linear peptides, homogenous peptide dimers and hetero bivalent peptides were designed for site-specific recognition of human serum albumin (HSA). Three hydrophilic regions located at different subdomains of HSA were chosen as targets for the molecular design. The binding affinity, selectivity and kinetics of the candidates were screened with surface plasmon resonance imaging (SPRi) and fluoroimmuno assays. Benefiting from the synergistic effect from the surface-targeted peptide binders and the flexible spacer, a heterogenetic dimer peptide (heter-7) with fast binding and slow dissociation behavior was identified as the optimized probe. Heter-7 specifically recognizes the target protein HSA, and effectively blocks the binding of antibody to HSA. Its inhibitory activity was estimated as 83 nM. It is noteworthy that heter-7 can distinguish serum albumins from different species despite high similarities in sequence and structure of these proteins. This hetero bivalent peptide shows promise for use in serum proteomics, disease detection and drug transport, and provides an effective approach for promoting the affinity and selectivity of ligands to achieve desirable chemical and biological outcomes.
Co-reporter:Le Sheng, Yulong Jin, Yonghuan He, Yanyan Huang, Liushui Yan, Rui Zhao
Talanta 2017 Volume 174(Volume 174) pp:
Publication Date(Web):1 November 2017
DOI:10.1016/j.talanta.2017.07.002
•Magnetic core-shell MIPs were fabricated via si-RAFT polymerization.•MIPs were applied for the selective enrichment of 2,4-D in real samples.•A well-defined polymer shell with fast mass transfer was fabricated.•The material revealed high specificity and affinity towards 2,4-D over analogues.Superparamagnetic core-shell molecularly imprinted polymer nanoparticles (MIPs) were prepared via surface initiated reversible-addition fragmentation chain transfer (si-RAFT) polymerization for the selective recognition of 2,4-dichlorophenoxyacetic acid (2,4-D) in real samples. The construction of uniform core-shell structure with a 50 nm MIP layer was successfully accomplished, which favored mass transfer and resulted in fast recognition kinetics. The static equilibrium experiments revealed the satisfied adsorption capacity and imprinting efficiency of Fe3O4@MIP. Moreover, the Fe3O4@MIP exhibited high selectivity and affinity towards 2,4-D over structural analogues. The prepared Fe3O4@MIP nanoparticles were used for the selective enrichment of 2,4-D in tap water and Chinese cabbage samples. Combined with RP-HPLC, the recoveries of 2,4-D were calculated from 93.1% to 103.3% with RSD of 1.7–5.4% (n = 3) in Chinese cabbage samples. This work provides a versatile approach for fabricating well-constructed core-shell MIP nanoparticles for rapid enrichment and highly selective separation of target molecules in real samples.Download high-res image (142KB)Download full-size image
Co-reporter:Yang Yu, Yanyan Huang, Fang Hu, Yulong Jin, Guanxin Zhang, Deqing Zhang, and Rui Zhao
Analytical Chemistry 2016 Volume 88(Issue 12) pp:6374
Publication Date(Web):May 27, 2016
DOI:10.1021/acs.analchem.6b00774
Smart and versatile nanostructures have demonstrated their effectiveness for biomolecule analysis and show great potential in digging insights into the structural/functional relationships. Herein, a nanoscale molecular self-assembly was constructed for probing the site-specific recognition and conformational changes of human serum albumin (HSA) with tunable size and emission. A tetraphenylethylene derivative TPE-red-COOH was used as the building block for tailoring fluorescence-silent nanoparticles. The highly specific and sensitive response to HSA was witnessed by the fast turn-on of the red fluorescence and simultaneous disassembly of the nanostructures, whereas various endogenous biomolecules cannot induce such response. The mechanism investigation indicates that the combination of multiple noncovalent interactions is the driving force for disassembling and trapping TPE-red-COOH into HSA. The resultant restriction of intramolecular rotation of TPE-red-COOH in the hydrophobic cavity of HSA induces the significant red emission. By using the fluorescence activatable nanosensor as the structural indicator, the stepwise conformational transitions of HSA during denaturing and the partial refolding of subdomain IIA of HSA were facilely visualized. Benefiting from its activatable signaling, sensitivity, and simplicity, such molecular assembly provides a kind of soft nanomaterial for site-specific biomolecule probing and conformational transition detection concerning their structure, function, and biomedical characteristics.
Co-reporter:Yanyan Huang;Yulong Jin
Science China Chemistry 2016 Volume 59( Issue 10) pp:1250-1257
Publication Date(Web):2016 October
DOI:10.1007/s11426-016-0186-x
The complicated, highly dynamic and diverse nature of biosystems brings great challenges to the specific analysis of molecular processes of interest. Nature provides antibodies for the specific recognition of antigens, which is a straight-forward way for targeted analysis. However, there are still limitations during the practical applications due to the big size of the antibodies, which accelerate the discovery of small molecular probes. Peptides built from various optional building blocks and easily achieved by chemical synthetic approaches with predictable conformations, are versatile and can act as tailor-made targeting vehicles. In this mini review, we summarize the recent developments in the discovery of novel peptides for bioanalytical and biomedical applications. Progresses in peptide-library design and selection strategies are presented. Recent achievements in the peptide-guided detection, imaging and disease treatment are also focused.
Co-reporter:Yulong Jin, Yanyan Huang, Hua Yang, Guoquan Liu and Rui Zhao
Chemical Communications 2015 vol. 51(Issue 77) pp:14454-14457
Publication Date(Web):05 Aug 2015
DOI:10.1039/C5CC05184C
A peptide-guided prodrug incorporating a tumor-specific peptide, doxorubicin, and a pH-sensitive hydrazone bridge was developed for targeted ablation of cancer cells with minimal side cytotoxicity.
Co-reporter:Yanyan Huang, Qundan Zhang, Guoquan Liu and Rui Zhao
Chemical Communications 2015 vol. 51(Issue 30) pp:6601-6604
Publication Date(Web):10 Mar 2015
DOI:10.1039/C5CC00885A
A flow injection analysis–quartz crystal microbalance (FIA–QCM) biosensor was developed for probing the dynamic interactions during protease inhibition. Being sensitive to conformation features of different proteases, this continuous-flow sensor has potential for structural–functional analysis and inhibitor selection.
Co-reporter:Shilang Gui, Yanyan Huang, Fang Hu, Yulong Jin, Guanxin Zhang, Liushui Yan, Deqing Zhang, and Rui Zhao
Analytical Chemistry 2015 Volume 87(Issue 3) pp:1470
Publication Date(Web):January 20, 2015
DOI:10.1021/ac504153c
Herein, a new fluorescence turn-on chemosensor 2-(4-(1,2,2-triphenylvinyl)phenoxy)acetic acid (TPE-COOH) specific for Al3+ was presented by combining the aggregation-induced-emission (AIE) effect of tertaphenylethylene and the complexation capability of carboxyl. The introduction of carboxylic group provides the probe with good water-solubility which is important for analyzing biological samples. The recognition toward Al3+ induced the molecular aggregation and activated the blue fluorescence of the TPE core. The high selectivity of the probe was demonstrated by discriminating Al3+ over a variety of metal ions in a complex mixture. A detection limit down to 21.6 nM was determined for Al3+ quantitation. Furthermore, benefiting from its good water solubility and biocompatibility, imaging detection and real-time monitoring of Al3+ in living HeLa cells were successfully achieved. The AIE effect of the probe enables high signal-to-noise ratio for bioimaging even without multiple washing steps. These superiorities make this probe a great potential for the functional study and analysis of Al3+ in complex biosystems.
Co-reporter:Yonghuan He, Yanyan Huang, Yulong Jin, Xiangjun Liu, Guoquan Liu, and Rui Zhao
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 12) pp:9634
Publication Date(Web):May 23, 2014
DOI:10.1021/am5020666
The construction of molecularly imprinted polymers on magnetic nanoparticles gives access to smart materials with dual functions of target recognition and magnetic separation. In this study, the superparamagnetic surface-molecularly imprinted nanoparticles were prepared via surface-initiated reversible addition–fragmentation chain transfer (RAFT) polymerization using ofloxacin (OFX) as template for the separation of fluoroquinolones (FQs). Benefiting from the living/controlled nature of RAFT reaction, distinct core–shell structure was successfully constructed. The highly uniform nanoscale MIP layer was homogeneously grafted on the surface of RAFT agent TTCA modified Fe3O4@SiO2 nanoparticles, which favors the fast mass transfer and rapid binding kinetics. The target binding assays demonstrate the desirable adsorption capacity and imprinting efficiency of Fe3O4@MIP. High selectivity of Fe3O4@MIP toward FQs (ofloxacin, pefloxacin, enrofloxacin, norfloxacin, and gatifloxacin) was exhibited by competitive binding assay. The Fe3O4@MIP nanoparticles were successfully applied for the direct enrichment of five FQs from human urine. The spiked human urine samples were determined and the recoveries ranging from 83.1 to 103.1% were obtained with RSD of 0.8–8.2% (n = 3). This work provides a versatile approach for the fabrication of well-defined MIP on nanomaterials for the analysis of complicated biosystems.Keywords: core−shell; fluoroquinolones; human urine; molecularly imprinted polymer; reversible addition−fragmentation chain transfer polymerization; superparamagnetic;
Co-reporter:Fang Hu, Yanyan Huang, Guanxin Zhang, Rui Zhao, Hua Yang, and Deqing Zhang
Analytical Chemistry 2014 Volume 86(Issue 15) pp:7987
Publication Date(Web):July 7, 2014
DOI:10.1021/ac502103t
A new red-emissive bioprobe TPE-red-2AP2H was developed by taking advantage of the unique emission feature of tetraphenylethylene and a cancer cell-specific peptide. By responding to the target protein and the acidic microenvironment of tumor cells, activated fluorescence bioimaging was achieved with high signal-to-noise ratio and without involving mutiple washing steps. Apart from targeting the membrane-anchored LAPTM4B proteins, TPE-red-2AP2H was successfully utilized to trace the intracellular movement of LAPTM4B protein. The generation of 1O2 under visible light irradiation makes this bioprobe also promising for targeted-photodynamic therapy. By discriminating the expression level of the target protein, TPE-red-2AP2H can respond to the progression status of tumors with different photodynamic therapy effect.
Co-reporter:Yongliang Liu, Yonghuan He, Yulong Jin, Yanyan Huang, Guoquan Liu, Rui Zhao
Journal of Chromatography A 2014 Volume 1323() pp:11-17
Publication Date(Web):3 January 2014
DOI:10.1016/j.chroma.2013.11.002
•Monodispersed macroporous core–shell PGMA@MIP particles for 2,4-dichlorophenoxyacetic acid (2,4-D) were prepared via si-ATRP.•Monodispersed macroporous PGMA particles were synthesized as the supporting matrix.•PGMA@MIP exhibited excellent selectivity, accessibility and affinity toward 2,4-D.•PGMA@MIP particles were used to selectively enrich 2,4-D from tap water.Porous polymers have aroused extensive attention due to their controllable porous structure in favor of mass transfer and binding capacity. In this work, the novel macroporous core–shell molecularly imprinted polymers (MIP) for selective recognition of 2,4-dichlorophenoxyacetic acid (2,4-D) were prepared by surface initiated atom transfer radical polymerization (si-ATRP). By using one-step swelling and polymerization method, the monodispersed macroporous poly(glycidyl methacrylate) (PGMA) particles were synthesized and used as supporting matrix for preparing surface MIP particles (PGMA@MIP). Thanks to the inner and outer surface-located binding cavities and the macroporous structure, the PGMA@MIPs revealed desirable efficiency for template removal and mass transfer, and thus excellent accessibility and affinity toward template 2,4-D. Moreover, PGMA@MIPs exhibited much higher selectivity toward 2,4-D than PGMA@NIPs. PGMA@MIP particles were directly used to selectively enrich 2,4-D from tap water and the recoveries of 2,4-D were obtained as 90.0–93.4% with relative standard division of 3.1–3.4% (n = 3). The macroporous PGMA@MIPs also possessed steady and excellent reusable performance for 2,4-D in four extraction/stripping cycles. This novel macroporous core–shell imprinted material may become a powerful tool for rapid and efficient enrichment and separation of target compounds from the complicated samples.
Co-reporter:Yunfeng Xie;Yulong Jin;Yanyan Huang;Guoquan Liu
Microchimica Acta 2014 Volume 181( Issue 13-14) pp:1521-1527
Publication Date(Web):2014 October
DOI:10.1007/s00604-014-1208-7
A novel quartz crystal microbalance (QCM) sensor has been developed for highly selective and sensitive detection of Pb2+ by exploiting the catalytic effect of Pb2+ ions on the leaching of gold nanoparticles from the surface of a QCM sensor. The use of self-assembled gold nanoparticles (AuNPs) strongly enlarges the size of the interface and thus amplifies the analytical response resulting from the loss of mass. This results in a very low detection limit for Pb2+ (30 nM). The high selectivity is demonstrated by studying the effect of potentially interfering ions both in the absence and presence of Pb2+ ions. This simple and well reproducible sensor was applied to the determination of lead in the spiked drinking water. This work provides a novel strategy for fabricating QCM sensors towards Pb2+ in real samples.
Co-reporter:Dr. Yanyan Huang;Fang Hu; Rui Zhao;Dr. Guanxin Zhang;Dr. Hua Yang; Deqing Zhang
Chemistry - A European Journal 2014 Volume 20( Issue 1) pp:158-164
Publication Date(Web):
DOI:10.1002/chem.201303679
Abstract
Smart molecular probes and flexible methods are attracting remarkable interest for the visualization of cancer-related biological and chemical events. In this work, a new fluorescence turn-on probe with dual-recognition characteristics for the specific imaging of cancer cells is reported. This new bioprobe is rationally designed by linking tetraphenylethylene (TPE), an aggregation-induced emission (AIE) fluorophore, with the small peptide IHGHHIISVG (referred to as AP2H), a targeting ligand to the broad-spectrum cancer-related protein LAPTM4B. The binding of the probe TPE-AP2H with the target, both in solution and at the cellular level, switches on the fluorescence of TPE because of the inhibition of internal rotations within the TPE framework. Accordingly, this bioprobe allows the real-time monitoring and subcellular localization of LAPTM4B in cancer cells, with a very high target-to-background ratio for the imaging. Furthermore, brighter fluorescence images are detected after incubation of TPE-AP2H with tumor cells at lower pH values. Thus, this new bioprobe is more advantageous because it can simultaneously target the LAPTM4B protein and sense the characteristic low-pH environment of tumor cells. In addition, TPE-AP2H displays high photostability and low cytotoxicity. Therefore, this new bioprobe is promising for the more accurate and reliable imaging of tumor markers in live cancer cells.
Co-reporter:Weizhi Wang, Yanyan Huang, Yulong Jin, Guoquan Liu, Yi Chen, Huimin Ma and Rui Zhao
Analyst 2013 vol. 138(Issue 10) pp:2890-2896
Publication Date(Web):08 Mar 2013
DOI:10.1039/C3AN00463E
A novel integrated microfluidic system was designed and fabricated for affinity peptide screening with in situ detection. A tetra-layer microfluidic hybrid chip containing two top eccentric diffluent layers, an inter-layer and a bottom screening layer, was developed as the core device of the system. The eccentric diffluent layers were ingeniously invented for the vertical sample delivery from 2 top-inlets into 12 bottom-inlets, which eliminated the use of excessive accessories and complicated pipelines currently used in other systems. By using six pH gradient generators, the magnetic bead-based screening in 36 parallel chambers was simultaneously carried out under 6 different pH conditions from 5.4 to 8.2. This allowed simultaneous screening of 6 compounds and each under 6 different pH conditions. The fabricated chip system was applied to screening of affinity peptides towards β-endorphin antibody. The affinities of the peptide ligands to the antibody were assessed by on-chip confocal detection. The results from the screening study using this system indicated that the pentapeptide with the sequence of YGGFL had the highest affinity towards β-endorphin antibody at pH 7.1, which was further confirmed by the ELISA assay using a 96-well plate format. This microfluidic screening system is automatic, low-cost and reusable for not only peptide screening but also other bioactive compounds screening towards target molecules.
Co-reporter:Yulong Jin, Yanyan Huang, Guoquan Liu and Rui Zhao
Analyst 2013 vol. 138(Issue 18) pp:5479-5485
Publication Date(Web):01 Jul 2013
DOI:10.1039/C3AN00948C
A novel quartz crystal microbalance (QCM) sensor for rapid, highly selective and sensitive detection of copper ions was developed. As a signal amplifier, gold nanoparticles (Au NPs) were self-assembled onto the surface of the sensor. A simple dip-and-dry method enabled the whole detection procedure to be accomplished within 20 min. High selectivity of the sensor towards copper ions is demonstrated by both individual and coexisting assays with interference ions. This gold nanoparticle mediated amplification allowed a detection limit down to 3.1 μM. Together with good repeatability and regeneration, the QCM sensor was also applied to the analysis of copper contamination in drinking water. This work provides a flexible method for fabricating QCM sensors for the analysis of important small molecules in environmental and biological samples.
Co-reporter:Yongliang Liu, Yanyan Huang, Jizhong Liu, Weizhi Wang, Guoquan Liu, Rui Zhao
Journal of Chromatography A 2012 Volume 1246() pp:15-21
Publication Date(Web):13 July 2012
DOI:10.1016/j.chroma.2012.01.045
The novel superparamagnetic surface molecularly imprinted Fe3O4@MIP nanoparticles for water-soluble pefloxacin mesylate (PEF-M) were prepared via surface initiated atom transfer radical polymerization (si-ATRP). The binary mixture of methanol and water was selected as the polar solvents for fabricating PEF-M imprinted MIPs. The Fe3O4@MIP exhibited high saturation magnetization of 41.4 emu/g leading to the fast separation. The adsorption behaviors indicated that the Fe3O4@MIP nanoparticles possessed specific recognition and high affinity towards template PEF-M in aqueous media. Moreover, Fe3O4@MIP nanoparticles were directly used to selectively enrich PEF-M from egg samples. By RP-HPLC analysis, the recoveries of PEF-M were obtained as 92.8–96.5% with relative standard division of 2.4–4.0%.Highlights► Fe3O4@MIP nanoparticles for water-soluble pefloxacin mesylate were prepared via ATRP. ► Fe3O4@MIP exhibited the excellent recognition ability to PEF-M in aqueous media. ► Fe3O4@MIP nanoparticles were used to selectively enrich PEF-M from egg samples. ► Imprinting water-soluble small molecules using high polar media via si-ATRP.
Co-reporter:Yulong Jin, Yanyan Huang, Yunfeng Xie, Wenbing Hu, Fuyi Wang, Guoquan Liu, Rui Zhao
Talanta 2012 Volume 89() pp:531-536
Publication Date(Web):30 January 2012
DOI:10.1016/j.talanta.2011.12.070
The cyclic oxidation and reduction of methionine (Met) containing peptides and proteins play important roles in biological system. This work was contributed to analysis the cyclic oxidation and reduction processes of a methionine containing peptide which is very likely to relate in the cell signal transduction pathways. To mimic the biological oxidation condition, hydrogen peroxide was used as the reactive oxygen species to oxidize the peptide. Reversed-phase high-performance liquid chromatography and mass spectrometry were employed to monitor the reactions and characterize the structural changes of the products. A rapid reduction procedure was developed by simply using KI as the reductant, which is green and highly efficient. By investigation of the cyclic oxidation and reduction process, our work provides a new perspective to study the function and mechanism of Met containing peptides and proteins during cell signaling processes as well as diseases.Highlights► The cyclic oxidation and reduction of methionine (Met) containing peptides and proteins. ► Structural changes monitored by RP-HPLC, MALDI-TOF MS and ESI MS/MS. ► A rapid, highly efficient and universal reduction method. ► The interconversion of the Met containing peptide implies its importance during cancer signaling.
Co-reporter:Jizhong Liu, Weizhi Wang, Yunfeng Xie, Yanyan Huang, Yongliang Liu, Xiangjun Liu, Rui Zhao, Guoquan Liu and Yi Chen
Journal of Materials Chemistry A 2011 vol. 21(Issue 25) pp:9232-9238
Publication Date(Web):20 May 2011
DOI:10.1039/C1JM10227C
The superparamagnetic surface molecularly imprinted Fe3O4@MIP nanoparticles for bisphenol A (BPA) were prepared via surface initiated atom transfer radical polymerization (si-ATRP). The Fe3O4 core was compactly encapsulated with a polychloromethylstyrene (PCMS) layer viamini-emulsion polymerization. Fe3O4@MIP exhibited superparamagnetic property with saturation magnetization of 25.2 emu g−1. The BPA imprinted Fe3O4@MIP revealed specific selectivity and high affinity to the template BPA over structural analogues. Moreover, the surface-imprinted MIP nanoparticles showed good site accessibility for BPA. The compactly PCMS-coated Fe3O4@MIP maintained its response ability to a magnetic field at acidic and alkaline conditions. Fe3O4@MIP was used to determine BPA in tap water samples with good accuracy and precision.
Co-reporter:Yanyan Huang, Shaoxiang Xiong, Guoquan Liu and Rui Zhao
Chemical Communications 2011 vol. 47(Issue 29) pp:8319-8321
Publication Date(Web):20 Jun 2011
DOI:10.1039/C1CC12303C
A simple, rapid and highly selective method has been developed for the direct visual detection of tryptophan in a mixture of amino acids or in a protein based on DMSO acceleration.
Co-reporter:Weizhi Wang, Yanyan Huang, Jizhong Liu, Yunfeng Xie, Rui Zhao, Shaoxiang Xiong, Guoquan Liu, Yi Chen and Huimin Ma
Lab on a Chip 2011 vol. 11(Issue 5) pp:929-935
Publication Date(Web):26 Jan 2011
DOI:10.1039/C0LC00542H
A novel integrated continuous-flow microfluidic system was designed and fabricated for solid phase peptide synthesis (SPPS) using conventional reactants. The microfluidic system was composed of a glass-based radial reaction chip, a diffluent chip, amino acid feeding reservoirs and continuous-flow reagent pathways. A tri-row cofferdam-fence structure was designed for solid phase supports trapping. Highly cross-linked, porous and high-loading 4-(hydroxymethyl)phenoxymethyl polystyrene (HMP) beads were prepared for microfluidic SPPS. The transfer losses, hazardous handling and time-consuming processes in traditional peptide cleavage steps were avoided by being replaced with the on-chip cleavage treatment. Six peptides from an antibody affinity peptide library against β-endorphin with different lengths and sequences were obtained simultaneously on the constructed continuous-flow microfluidic system within a short time. This microfluidic system is automatic, integrated, effective, low-cost, recyclable and environment-friendly for not only SPPS but also other solid phase chemical syntheses.
Co-reporter:Yunfeng Xie, Yanyan Huang, Weizhi Wang, Guoquan Liu and Rui Zhao
Analyst 2011 vol. 136(Issue 12) pp:2482-2488
Publication Date(Web):11 May 2011
DOI:10.1039/C1AN15119C
The dynamic interaction between melamine (M) and cyanuric acid (CA) in artificial urine was investigated by a flow injection analysis-quartz crystal microbalance (FIA-QCM) system. Melamine was used as the recognition element and immobilized onto the QCM gold surface. The process of M and CA interaction was recorded by FIA-QCM in real-time. The multilayer complex of M and CA was successfully formed on the crystal surface of the QCM when CA and M were introduced into the FIA-QCM system alternately. The influence of pH on the M and CA interaction indicated that the M–CA multilayer complex possesses high stability over a wide range of pH values, especially in physiological urine condition. The association and dissociation rate constants were determined under artificial urine condition and the association constant for M and CA was calculated as 102 L mol−1. The M–CA complex was further characterized by Fourier transform infrared spectroscopy (FT-IR) and atomic force microscopy (AFM). Mechanism study suggested that the formation of the multilayer complex in artificial urine was mainly attributed to the intermolecular hydrogen bonding between M and CA. The work provides direct insight into the dynamic interaction between M and CA under physiological conditions and would be helpful for the research of kidney stones induced by melamine contamination.
Co-reporter:Dr. Yanyan Huang; Dr. Rui Zhao;Yabin Fu;Dr. Qundan Zhang; Dr. Shaoxiang Xiong;Dr. Li Li; Rouli Zhou; Guoquan Liu; Dr. Yi Chen
ChemBioChem 2011 Volume 12( Issue 8) pp:1209-1215
Publication Date(Web):
DOI:10.1002/cbic.201100031
Abstract
Specific detection and in vivo tracing of cancer biomarkers are important for cancer analysis. In this work, a simple and effective strategy for developing peptide probes was established. Peptides were rationally designed by using an antisense peptide approach directed towards an extracellular fragment (EL2) of a novel tumor-related protein LAPTM4B. Positional-scanning and stepwise affinity screening was employed to obtain an optimal peptide AP2H (IHGHHIISVG). The dissociation constant between the two small peptides, AP2H and the target EL2, was 5.51 μM under physiological conditions. Fluorescence imaging assays indicated that AP2H can recognize live hepatoma cells by targeting the LAPTM4B protein on the cell surface with high specificity, low cytotoxicity and desirable cell penetrability. Compared to negative control cells, AP2H could differentiate cells with different expression levels of LAPTM4B. The screened peptide probe for molecular signatures of cancer cells, based on targeting the LAPTM4B protein, has potential applications in cancer diagnosis and targetable drug delivery.
Co-reporter:Xiangjun Liu, Jizhong Liu, Yanyan Huang, Rui Zhao, Guoquan Liu, Yi Chen
Journal of Chromatography A 2009 Volume 1216(Issue 44) pp:7533-7538
Publication Date(Web):30 October 2009
DOI:10.1016/j.chroma.2009.06.018
A pseudo template molecularly imprinted polymer (MIP) was prepared for methotrexate (MTX) and a RP-HPLC method combined with the MIP was developed for the determination of MTX in human serum. Because of the poor solubility of MTX in common MIP preparation solvents, trimethoprim (TMP), a molecule having the similar imprinting sites as MTX, is selected as the pseudo template. The MIP was prepared using methacrylic acid (MAA) and ethylene glycol dimethacrylate as functional monomer and cross-linker, respectively. 1H NMR study showed highly strong interaction between TMP and MAA with hydrogen bonds. Chromatographic behaviors indicated that the TMP-MIP possessed excellent affinity and selectivity for MTX. And the imprinting factor for MTX was high up to 9.5 when 7:3 of acetonitrile:methanol (v/v) was used as mobile phase. Moreover, TMP-MIP was used as the solid-phase extraction (SPE) material to enrich the target compound MTX in human serum samples for HPLC analysis. The SPE process was carefully optimized and good recoveries of MTX were obtained as 81.6–86.2% with RSD of 0.22–1.84% when the spiked concentration of MTX was 2.0–10.0 μg mL−1 in human serum samples. The results indicated that the pseudo template MIP can be applied to preconcentration, purification and analysis of MTX in clinic samples.
Co-reporter:Qundan Zhang, Yanyan Huang, Rui Zhao, Guoquan Liu, Yi Chen
Journal of Colloid and Interface Science 2008 Volume 319(Issue 1) pp:94-99
Publication Date(Web):1 March 2008
DOI:10.1016/j.jcis.2007.11.039
A novel biosensor for detecting antithrombin III (AT III) was constructed based on in situ growth of nanogold on the gold electrode of quartz crystal microbalance (QCM). The growth process of nanogold was monitored by QCM in real time. Heparin was used as the affinity ligand and immobilized onto the nanogold modified gold electrode. A flow injection analysis–quartz crystal microbalance (FIA-QCM) system was used to investigate the relationship between nanogold growth and the AT III response. Along with the nanogold particle growth within initial 5 min, the amount of heparin immobilized onto the nanogold modified electrode increased quickly. Correspondingly, the frequency response to AT III binding increased rapidly at the same time. After that, both the immobilized amount of heparin and the sensor response to AT III decreased gradually. Compared with the directly immobilized large nanogold particles, the in situ grown particles with the same size occupy more sensor surface, resulting in higher frequency shifts to AT III in the interaction study between heparin and AT III. The obtained constants of AT III binding to immobilized heparin are kass=(1.65±0.12)×103 L/mols, kdiss=(2.63±0.18)×10−2 1/skdiss=(2.63±0.18)×10−2 1/s and KA=(6.27±0.42)×104 L/molKA=(6.27±0.42)×104 L/mol.In situ growth of nanogold on quartz crystal microbalance was realized for enhancing the sensor response and applied to determine the interaction between heparin and antithrombin III.
Co-reporter:Yanyan Huang;Jia Luo;Shaoxiang Xiong;Dihua Shangguan;Hongwu Zhang;Guoquan Liu ;Yi Chen
Journal of Molecular Recognition 2008 Volume 21( Issue 2) pp:122-131
Publication Date(Web):
DOI:10.1002/jmr.880
Abstract
A combination of high-performance affinity chromatography and antisense peptide based combinatorial peptide libraries was used to screen a potential inhibitor for SARS-CoV. An aromatic-amino acid-rich region within the transmembrane domain at the C terminal of spike (S) protein identified as a membrane-active region was chosen as the target sense peptide (SP) and immobilized as affinity ligand. Four antisense peptides were designed based on the degeneracy of genetic codes. One of them was screened as the lead peptide to construct the extended peptide libraries (EPL). The library screening was carried out at pH 5.5 so as to mimic the low-pH milieu required by virus fusion. After five cycles of screening, a dodecapeptide KKKKYRNIRRPG (DP) was identified to possess the highest binding affinity to the immobilized sense peptide. The dissociation constant of the complex between the DP and the SP was 5.64 × 10−7 M in a physiological condition. The recognition between the DP and recombinant SARS S protein was demonstrated by ELISA assay to be in a saturable way. The competitive inhibition of the sense peptide in the competitive ELISA reveals the affinity binding between the DP and SARS S protein is specific and directed towards the target SP of the S protein. The results indicate this preferred polypeptide can be used as a lead compound of potent inhibitor of SARS-CoV. The mechanism study suggests the specific recognition between the DP and the target peptide was due to sequence-dependent and multi-modal affinity interaction. Copyright © 2008 John Wiley & Sons, Ltd.
Co-reporter:Jia Luo, Qundan Zhang, Yanyan Huang, Guoquan Liu, Rui Zhao
Analytica Chimica Acta 2007 Volume 590(Issue 1) pp:91-97
Publication Date(Web):2 May 2007
DOI:10.1016/j.aca.2007.03.022
Quartz crystal microbalance (QCM) biosensors for recombinant human interferon-β (rhIFN-β) were constructed by utilizing antisense peptides adhering to the QCM gold surfaces. Two antisense peptides, both corresponding to the N-terminal fragment 1–14 of rhIFN-β, were used in this study. Antisense peptide AS-1 was the original antisense peptide and AS-2 was the modified antisense peptide based on the antisense peptide degeneracy. Both antisense peptides were immobilized on the gold electrodes of piezoelectric crystals, respectively, via a self-assembling monolayer of 1,2-ethanedithiol. The binding affinity between rhIFN-β and each immobilized antisense peptide in solution was evaluated using a quartz crystal microbalance-flow injection analysis (QCM-FIA) system. The dissociation constant of rhIFN-β on the antisense peptide AS-1 and AS-2 biosensor was (1.89 ± 0.101) × 10−4 and (1.22 ± 0.0479) ×10−5 mol L−1, respectively. The results suggested that AS-2 had a higher binding affinity to rhIFN-β than AS-1. The detection for rhIFN-β using each biosensor was precise and reproducible. The linear response ranges of rhIFN-β binding to both biosensors were same with a concentration range of 0.12–0.96 mg mL−1. The results demonstrated the successful construction of highly selective QCM biosensors using antisense peptide approach, and also confirmed the feasibility of increasing antisense peptide binding affinity by appropriate sequence modification.
Co-reporter:Jia Luo;YanYan Huang;ShaoXiang Xiong;GuoQuan Liu
Science Bulletin 2007 Volume 52( Issue 10) pp:1311-1319
Publication Date(Web):2007 May
DOI:10.1007/s11434-007-0175-3
The specific interaction between sense and antisense peptides was studied by high-performance affinity chromatography (HPAC) and quartz crystal microbalance (QCM) biosensor. Fragment 1–14 of human interferon-β (hIFN-β) was chosen as sense peptide and its three antisense peptides (AS-IFN 1, AS-IFN 2, and AS-IFN 3) were designed according to the degeneracy of genetic codes. The affinity column was prepared with sense peptide as ligand and the affinity chromatographic behavior was evaluated. Glu-substituted antisense peptide (AS-IFN 3) showed the strongest binding to immobilized sense peptide at pH 7.5. A quartz crystal microbalance-flow injection analysis (QCM-FIA) system was introduced to investigate the recognition process in real-time. The equilibrium dissociation constants between sense peptide and AS-IFN 1, AS-IFN 2 and AS-IFN 3 measured 2.08×10−4, 1.31×10−4 and 2.22×10−5 mol/L, respectively. The mechanism study indicated that the specific recognition between sense peptide and AS-IFN 3 was due to sequence-dependent and multi-modal affinity interaction.
Co-reporter:Xiangjun Liu, Zhiyong Chen, Rui Zhao, Dihua Shangguan, Guoquan Liu, Yi Chen
Talanta 2007 Volume 71(Issue 3) pp:1205-1210
Publication Date(Web):28 February 2007
DOI:10.1016/j.talanta.2006.06.021
Uniform-sized molecularly imprinted polymer (MIP) beads for metsulfuron-methyl (MSM) were firstly prepared by one-step swelling and polymerization method using 4-vinylpyridine (4-VPY) and ethylene glycol dimethacrylate (EDMA) as functional monomer and cross-linker, respectively. The preparation was optimized by varying the ratio of MSM to 4-VPY. The chromatographic behaviors of MSM and other structurally related sulfonylureas (SUs) on the resultant MIP column were evaluated. The imprinted polymer revealed specific affinity to the template and the fair resolution of SUs was also obtained. Furthermore, the uniform-sized MSM-MIP was used as the solid phase extraction (SPE) material to enrich MSM in real water samples before reversed-phase HPLC (RP-HPLC) analysis. The recovery of MSM from 100 mL of drinking water at a 50 ng/L spike level was 99.59% with R.S.D. of 1.13%. The detection limit was about 6.0 ng/L of MSM when enriching a 100 mL water sample.
Co-reporter:Rui Zhao, Canliang Fang, Xiao Yu, Yang Liu, Jia Luo, Dihua Shangguan, Shaoxiang Xiong, Tiansheng Su, Guoquan Liu
Journal of Chromatography A 2005 Volume 1064(Issue 1) pp:59-66
Publication Date(Web):28 January 2005
DOI:10.1016/j.chroma.2004.12.023
The affinity inhibitor of fusion peptide of influenza A virus has been studied using a combination of high-performance affinity chromatography (HPAC) and combinatorial peptide libraries. Fusion peptide (FP) (1–11) of influenza A virus was used as the affinity ligand and immobilized onto the poly(glycidyl methacrylate) (PGMA) beads. Positional scanning peptide libraries based on antisense peptide strategy and extended peptide libraries were designed and synthesized. The screening was carried out at acidic pH (5.5) in order to imitate the environment of virus fusion. A hendecapeptide FHRKKGRGKHK was identified to have a strong affinity to the FP (1–11). The dissociation constant of the complex of the hendecapeptide and the FP (1–11) is 3.10 × 10−6 mol l−1 in a physiological buffer condition. The polypeptide has a fairly inhibitory effect on three different strains of influenza A virus H1N1 subtype.
Co-reporter:Rui Zhao, Jia Luo, Dihua Shangguan, Guoquan Liu
Journal of Chromatography B 2005 Volume 816(1–2) pp:175-181
Publication Date(Web):25 February 2005
DOI:10.1016/j.jchromb.2004.11.030
Viscose fiber, a regenerated cellulose, was evaluated for using as a novel matrix for high performance affinity chromatography. With a one-step activation with epichlorohydrin, heparin can be readily covalently attached to the matrix. This heparin–viscose fiber material was used for purifying antithrombin III (AT III) from human plasma. The purity of the AT III from this one-step purification is 93% as measured by SDS-PAGE and the protein recovery yield is about 90%. This column is highly specific as described by the dissociation constant of the complex of immobilized heparin and AT III, which was 2.83 × 10−5 mol/L. And more important, this viscose fiber material demonstrated its excellent mechanical property that allows the flow rate to reach up to 900 cm/h or more.
Co-reporter:Yanyan Huang, Qundan Zhang, Guoquan Liu and Rui Zhao
Chemical Communications 2015 - vol. 51(Issue 30) pp:NaN6604-6604
Publication Date(Web):2015/03/10
DOI:10.1039/C5CC00885A
A flow injection analysis–quartz crystal microbalance (FIA–QCM) biosensor was developed for probing the dynamic interactions during protease inhibition. Being sensitive to conformation features of different proteases, this continuous-flow sensor has potential for structural–functional analysis and inhibitor selection.
Co-reporter:Yulong Jin, Yanyan Huang, Hua Yang, Guoquan Liu and Rui Zhao
Chemical Communications 2015 - vol. 51(Issue 77) pp:NaN14457-14457
Publication Date(Web):2015/08/05
DOI:10.1039/C5CC05184C
A peptide-guided prodrug incorporating a tumor-specific peptide, doxorubicin, and a pH-sensitive hydrazone bridge was developed for targeted ablation of cancer cells with minimal side cytotoxicity.
Co-reporter:Yanyan Huang, Shaoxiang Xiong, Guoquan Liu and Rui Zhao
Chemical Communications 2011 - vol. 47(Issue 29) pp:NaN8321-8321
Publication Date(Web):2011/06/20
DOI:10.1039/C1CC12303C
A simple, rapid and highly selective method has been developed for the direct visual detection of tryptophan in a mixture of amino acids or in a protein based on DMSO acceleration.
Co-reporter:Jizhong Liu, Weizhi Wang, Yunfeng Xie, Yanyan Huang, Yongliang Liu, Xiangjun Liu, Rui Zhao, Guoquan Liu and Yi Chen
Journal of Materials Chemistry A 2011 - vol. 21(Issue 25) pp:NaN9238-9238
Publication Date(Web):2011/05/20
DOI:10.1039/C1JM10227C
The superparamagnetic surface molecularly imprinted Fe3O4@MIP nanoparticles for bisphenol A (BPA) were prepared via surface initiated atom transfer radical polymerization (si-ATRP). The Fe3O4 core was compactly encapsulated with a polychloromethylstyrene (PCMS) layer viamini-emulsion polymerization. Fe3O4@MIP exhibited superparamagnetic property with saturation magnetization of 25.2 emu g−1. The BPA imprinted Fe3O4@MIP revealed specific selectivity and high affinity to the template BPA over structural analogues. Moreover, the surface-imprinted MIP nanoparticles showed good site accessibility for BPA. The compactly PCMS-coated Fe3O4@MIP maintained its response ability to a magnetic field at acidic and alkaline conditions. Fe3O4@MIP was used to determine BPA in tap water samples with good accuracy and precision.
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