A novel bifunctional theranostic agent has been fabricated through the combination of acoustic responsive poly(lactic acid) microcapsules and near infrared absorbed gold nanorods that holds the potential of simultaneous ultrasound contrast diagnostic imaging and photothermal therapy.

An innovative photoresponsive cerasome is fabricated by sol–gel process in combination of self-assembly technique from a molecularly designed organoalkoxysilylated lipid containing an azobenzene unit, which is able to operate as a “valve” with an “on–off” function under specific stimuli to control the release of loaded guest molecules from the liposomal membrane.

We have constructed light-responsive polyelectrolyte microcapsules containing two different kinds of gold nanorods (Au-NRs) on their surface. We also show that they can act as a platform for active and selective release of the model drug Rhodamine 6G (Rh6G) contained in the microcapsules. The Au-NRs were first coated with poly(sodium styrene-4-sulfonate) and then adsorbed onto the surface of the capsules by electrostatic interaction. Confocal laser scanning microscopy reveals that near-infrared light irradiation at 800 nm induces the release of Rh6G from the microcapsules if the longitudinal surface plasmon resonance peak matches the excitation wavelength. In this case, irradiation also causes melting of nanorods as visualized by transmission electron microscopy. We presume that this method is of great value for in-vivo multi-drug delivery in combined therapies.

A novel electrochemical glucose biosensor was developed based on in situ covalent immobilization of glucose oxidase (GOx) by one-pot chitosan (CS)-incorporated sol–gel process in the presence of Prussian blue deposited multi-walled carbon nanotubes hybrids (PB/MWNTs) using 3-isocyanatopropyltriethoxysilane (ICPTES) as both a sol–gel precursor and a covalent coupling agent for GOx and CS. The electrode modified with the PB/MWNTs-GOx-CS-ICPTES sol–gel composite film showed good electrical conductivity and effective low-potential electron transfer mediation toward H2O2 reduction attributed to the incorporation of PB/MWNTs. The biosensor exhibited a linear response to glucose in the concentration range from 2.5 × 10−5 to 1.3 × 10−3 M with a correlation coefficient of 0.9998, a detection limit of 7.5 × 10−6 M, a low response time (10 s), good sensitivity and high anti-interference ability. Compared with the control biosensor based on the traditional tetraethoxysilane derived sol–gel composite film, the biosensor showed a similarly small apparent Michaelis–Menten constant of 3.67 mM but much higher electrochemical and biosensing stability.

Paclitaxel loaded cerasomes exhibited sophisticated controlled release behavior and remarkably high stability towards surfactant solubilization, long-term storage, acidic treatment, and all factors susceptible to destabilize conventional liposomes, demonstrating that liposomal nanohybrid cerasomes can be a new promising drug delivery system.

Amperometric biosensor is fabricated for the detection of carbaryl based on single walled carbon nanotubes (SWCNTs) and acetylcholine esterase (AchE). The dispersion of SWCNTs in positively charged polyelectrolyte, poly(diallyldimethylammonium chloride) (PDDA), possibly takes place due to weak supramolecular interaction between them, which then binds electrostatically to the negatively charged AchE at pH 7.4 using layer-by-layer (LbL) self-assembly technique. The optical intensity of UV/vis spectra increased with the number of layers, indicating the build up of a multilayer coating on the electrode. The activity of acetylcholine esterase on modified electrode of 3 mm in diameter was found to be 0.2 U. The biosensor showed good sensitivity and stability towards the monitoring of carbaryl pesticides in water with the detection limit of 10−12 g L−1 and recovery of 99.8 ± 2.7% to 10−10 g L−1. This protocol can be used for the immobilization of other enzymes to fabricate a range of biosensors.

Doxorubicin (DOX) conjugated magnetic silica nanoparticles (DOX–Fe3O4–SiO2) are successfully fabricated using a new one-pot method without need for the process of inconvenient multistep synthesis in advance, based on the condensation of DOX and the silica precursor 3-isocyanatopropyltriethoxysilane (ICPTES), followed by the spontaneous formation of a silica coating onto the surface of Fe3O4nanoparticlesvia sol–gel polymerization of triethoxysilane. Mass spectroscopy provides evidence that doxorubicin is conjugated to ICPTES via a urea bond (–NHCONH–) via the reaction of the amino groups of DOX with the isocyanate group (–NCO) of ICPTES in water. The obtained magnetic nanoparticles are well dispersed. Their mean diameter is about 66.9 nm with a narrow size distribution. The conjugated DOX–SiO2–Fe3O4nanoparticles exhibited a higher loading efficiency of 60.5 ± 3.7% and a more sustained release profile than SiO2nanoparticles containing physically-entrapped DOX. It is anticipated that fine-tuning of other drugs or bioactive molecules containing –NH2groups to Fe3O4/SiO2nanoparticles would foster innovative avenues for the development of smart drug delivery and controlled release systems.

A novel polymerized vesicular carrier loaded with paclitaxel was developed by introducing the ultraviolet (UV) cross-linkable 10,12-pentacosadiynoic acid (PCDA) into bilayered phospholipid vesicles with the purpose of improving the physicochemical stability as well as the controlled-release property of liposomes. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) results revealed the enhanced stability of PCDA-polymerized vesicles against Triton X-100. In particular, alteration in PCDA/phospholipids ratios and UV-irradiation time can modulate the cumulative paclitaxel released. For instance, vesicles composed of phospholipids only released 98.0 ± 2.1% of paclitaxel within 24 h. Over the same time period, 72.0 ± 5.8%, 43.9 ± 6.5%, and 20.1 ± 5.4% of paclitaxel was released from polymerized PCDA/phospholipid vesicles at molar ratios of 1:3, 1:1, and 3:1, respectively. Likewise, by increasing the UV-irradiation time from 20 to 40 min, the cumulative release of paclitaxel from polymerized PCDA/phospholipid vesicles at molar ratio of 1:1 decreased from 90.5 ± 3.7% to 37.6 ± 2.3% over a time period of experimental observation of 24 h. The influences of vesicle composition (i.e., PCDA/phospholipids ratio) and UV-irradiation time on the release rates of paclitaxel were further examined by finite element (FE) analyzed using Abaqus. Our results demonstrate that novel polymerized vesicles capable of regulating the release of anticancer drugs such as paclitaxel have been developed.

Iron−polysaccharide complex have been extensively utilized in the treatment of iron deficiency anemia for parenteral administration. Herein, a novel iron−heparin complexed hollow capsules with nanoscaled wall thickness have been fabricated by means of alternating deposition of ferric ions (III) (Fe3+) and heparin (Hep) onto the surface of submicroscaled (488 nm) and microscaled (10.55 μm) polystyrene latex particles via both electrostatic interaction and chemical complexation processes, followed by dissolution of the cores using tetrahydrofuran. Confocal micrographs and atomic force microscopy (AFM) images prove that iron−heparin complexed submicroscaled hollow capsules keep spherical shapes in solution and even after drying. The activated partial thromboplastin time (APTT) assay shows that complexing with ferric ions do not compromise the catalytic capacity of heparin to promote antithrombin III-mediated thrombin inactivation. The anticoagulant activity value of (Fe3+/Hep)8 capsules is evaluated to be about 95.7 U/mg, indicating that approximately 0.55 mg heparin was in 1 mg powder of submicroscaled (Fe3+/Hep)8 hollow capsules. Compared with the same dosage of heparin, iron−heparin complexed hollow capsules display a more prolonged anticoagulant duration than heparin. All these results reveal that such submicroscaled iron−heparin complexed hollow capsules have application potential as an injectable anticoagulant vehicle.

A novel bifunctional theranostic agent has been fabricated through the combination of acoustic responsive poly(lactic acid) microcapsules and near infrared absorbed gold nanorods that holds the potential of simultaneous ultrasound contrast diagnostic imaging and photothermal therapy.

An innovative photoresponsive cerasome is fabricated by sol–gel process in combination of self-assembly technique from a molecularly designed organoalkoxysilylated lipid containing an azobenzene unit, which is able to operate as a “valve” with an “on–off” function under specific stimuli to control the release of loaded guest molecules from the liposomal membrane.

Paclitaxel loaded cerasomes exhibited sophisticated controlled release behavior and remarkably high stability towards surfactant solubilization, long-term storage, acidic treatment, and all factors susceptible to destabilize conventional liposomes, demonstrating that liposomal nanohybrid cerasomes can be a new promising drug delivery system.