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Jianzhong Du

Publications and source records attributed to Jianzhong Du.

5 recordsLinked to original sources
PubMed2005

pH-sensitive vesicles based on a biocompatible zwitterionic diblock copolymer.

Highly biocompatible pH-sensitive diblock copolymer vesicles were prepared from the self-assembly of a biocompatible zwitterionic copolymer, poly[2-(methacryloyloxy)ethyl phosphorylcholine-block-2-(diisopropylamino)ethyl methacrylate], PMPC-b-PDPA. Vesicle formation occurred spontaneously by adjusting the solution pH from pH 2 to above 6, with the hydrophobic PDPA chains forming the vesicle walls. Transmission electron microscopy (TEM), dynamic laser light scattering (DLS), and UV-visible absorption spectrophotometry were used to characterize these vesicles. Gold nanoparticle-decorated vesicles were also obtained by treating the vesicles with HAuCl4, followed by NaBH4.

Biocompatible Materials↗
PubMed2005

pH-responsive vesicles based on a hydrolytically self-cross-linkable copolymer.

A new type of shape-persistent, pH-responsive vesicle was prepared by the self-assembly of a novel poly(ethylene oxide)-block-poly[2-(diethylamino)ethyl methacrylate-stat-3-(trimethoxysilyl)propyl methacrylate], PEO-b-P(DEA-stat-TMSPMA), copolymer. Vesicles were formed spontaneously in aqueous THF solution, with the hydrophilic PEO chains forming the corona and the pH-sensitive P(DEA-stat-TMSPMA) blocks being located in the membrane walls. Hydrolytic cross-linking within the hydrophobic membrane walls fixed the vesicle morphology. The resulting colloidally stable vesicles were characterized by 1H NMR, transmission electron microscopy (TEM), dynamic laser light scattering (DLS), and stopped-flow fluorescence experiments. The latter technique indicated that the permeability of the vesicle walls was sensitive to the pH of the aqueous solution, as expected. Gold-decorated vesicles were obtained by in situ reduction of AuCl4- anions to produce gold nanoparticles within the vesicle walls. (Yellow, hydrophilic PEO; green, pH-responsive DEA residues; blue, hydrolytically self-cross-linkable TMSPMA residues.)

Hydrogen-Ion Concentration↗
PubMed2005

Novel insect resistance in Brassica napus developed by transformation of chitinase and scorpion toxin genes.

Transgenic plants with introduced pest-resistant gene offer an efficient alternative insect control. The novel insect-resistant gene combination, chitinase(chi) and BmkIT(Bmk), containing an insect-specific chitinase gene and a scorpion insect toxin gene was introduced into Brassica napus cultivar via Agrobacterium-mediated transformation. Fifty-seven regenerated plantlets with kanamycin-resistance were obtained. Transgenic plants were verified by Southern blot analysis. Enzyme-linked immunosorbent assay (ELISA) and bioassay of artificial inoculation with diamondback moth (Plutella maculipenis) (DBM) larvae indicated that some of the transgenic plants were high-level expression for both chitinase and scorpion toxin proteins and performed high resistance against the tested pest infestation. The genetic analysis of T(1) progeny confirmed that the inheritance of introduced genes followed the Mendelian rules.

Animals↗
PubMed2003

Organic/inorganic hybrid vesicles based on a reactive block copolymer.

Presented in this communication is a novel hybrid vesicle with a cross-linked polyorganosiloxane wall based on a new reactive block copolymer, poly(ethylene oxide)-block-poly(3-(trimethoxysilyl)propyl methacrylate) (PEO-b-PTMSPMA), which was synthesized by atom transfer radical polymerization. The vesicles were prepared first by self-assembly of the block copolymer in a selective solvent, and then the PTMSPMA block was subjected to hydrolysis and polycondensation reaction to fix vesicle wall in the presence of triethylamine as a catalyst. Transmission electron microscopy, scanning electron microscopy, NMR, and light scattering have been used to characterize the vesicles.

Journal Article↗