Chitosan is an abundant and renewable polysaccharide, its derivatives exhibit attractive bioactivities and the wide applications in various biomedical fields. In this paper, two novel cationic chitosan derivatives modified with quaternary phosphonium salts were successfully synthesized via trimethylation, chloride acetylation, and quaternization with tricyclohexylphosphine and triphenylphosphin...

Interior tertiary amine groups of PAMAM-OH dendrimers (hydroxyl-terminated polyamidoamine, PAMAM) were modified by methylation to make these polymers have a more cationic character, which enabled electrostatic interaction between PAMAM-OH and plasmid DNA. A methylation reaction was dose-dependent, producing internally quaternized PAMAM-OH (QPAMAM-OH), thereby making tertiary amine/quaternary am...

As inspired by the Dot blot analysis, a well known technique in molecular biology and genetics for detecting biomolecules, a new paper-based platform for colorimetric detection of specific DNA sequences employing peptide nucleic acid (PNA) as a probe has been developed. In this particular study, a pyrrolidinyl PNA bearing a conformationally rigid d-prolyl-2-aminocyclopentanecarboxylic acid back...

Quaternary narcotic antagonists that are assumed not to penetrate the blood-brain barrier following systemic administration are commonly used to distinguish between peripheral and central actions of opiates. In mammals, these antagonists have a lower affinity for opioid receptors than their tertiary parent compounds. The relative affinity of quaternary vs. tertiary antagonists either for opioid...

W ITH perhaps one exception, decamethonium has been the parent of the main neuromuscular blocking agents introduced, since its discovery, for clinical trial as muscle-relaxants. Its descendants (see fig. 1) include suxamethonium (succinylcholine), suxethonium (362 I.S.), Ro 3-0386 and Laudolissin. The exception (fig. 2) is benzoquinonium (Mytolon), which was derived from an experimental anti-ba...

objective(s): drug delivery via mucosal routes has been confirmed to be effective in inducing strong immune responses. liposomes could enhance immune responses and mucoadhesive potentials, make them useful mucosal drug delivery systems. coating of liposomes by mucoadhesive polymers succeeded in enhancing immune responses. our studies aim at preparation and characterization of trimethylchitosan-...

In this work, the synthesis and solution self-assembly of partially fluorinated cationic polyelectrolytes based on post-polymerization-modified poly(2-(dimethylamino) ethyl methacrylate), incorporating hydrophobic groups along polymer chain, is reported. The post-polymerization modification aims to establish amphiphilic characteristics strong polyelectrolyte properties polymer. Therefore, self-...

The advanced water treatment taken by organic micro-pollution or microbiological pollution resource has been a hot issue of public concern. In this article, novel quaternary ammonium salt functionalized β-cyclodextrin polyurethane (QAS-β-CDPU) microparticles were successfully constructed for above-mentioned pollutants removal. By adjusting the proportion chlorine-containing monomers, we studied...