BACKGROUND Chitosan shows particularly high biocompatibility and fairly low cytotoxicity. However, chitosan is insoluble at physiological pH. Moreover, it lacks charge, so shows poor transfection. In order to develop a new type of gene vector with high transfection efficiency and low cytotoxicity, amphiphilic chitosan was synthesized and linked with low-molecular weight polyethylenimine (PEI). ...

Molecular mechanics and molecular dynamics simulations have been employed to characterise the interactions between SWNTs and biocompatible amphililic derivatives of chitosan, namely N-butyl-O-sulfate chitosan (NBSC), N-octyl-O-sulfate chitosan (NOSC) and N-palmitoyl-O-sulfate chitosan (NPSC). The computational simulations have shown that the affinity of the polymer for the hydrophobic surface o...

Objective N-octyl-N '- (2-carboxycyclohexanecarbonyl) -chitosan derivative (OCCC) was successfully synthesized. The analysis of the chitosan by infrared spectroscopy, nuclear magnetic resonance spectroscopy and like used to verify whether synthesis successful. To construct characterize nanoparticles with bovine serum albumin as model drug. transmission electron microscopy (TEM), encapsulation e...

Macromolecular drug carriers have attracted much attention taking advantage of passive tumor targeting property and excellent biocompatibility. For many biomedical applications, however, the effectiveness of the carriers is insufficient, which complicate further development into clinical use. Here, we systematically investigated the effects of molecular weight (from 1KDa to 300KDa) of macromole...

1. Conductivity and u.v. and visible spectroscopic techniques were used to investigate the solution structure of the prosthetic group of the ferric haemoproteins (ferrihaem) in dimethyl sulphoxide, NN-dimethylacetamide, NN-dimethylformamide and sulpholane, and certain of their aqueous mixtures. 2. In neutral or acid dimethyl sulphoxide, chlorohaemin is monomeric and completely dissociated into ...

The Front Cover shows chitin-derived oligosaccharides from marine biomass as powerful antimicrobial ‘weapon’ through the ‘booster’ containing formaldehyde. one-pot reaction of chitin with formaldehyde, an inexpensive bulk chemical, methylation and reduction reagent converts to N,N-dimethyl chitosan oligosaccharide (DMCOS), dramatically boosting its ‘damage output’ against fungus. conversion wit...

The mutagenic activities of several phthalate esters have been evaluated in an 8-azaguanine resistance assay in Salmonella typhimurium. Three phthalate esters were found to be mutagenic: dimethyl phthalate, diethyl phthalate and di-n-butyl phthalate. A number of other phthalate esters were not found to be mutagenic, including di(2-ethylhexyl) phthalate, di-n-octyl phthalate, diallyl phthalate, ...