Novel tailorable thiolated trimethylated chitosans for covalently stabilized nanoparticles

摘要

A novel method is presented to partially thiolate TMC with a high degree of quaternization (DQ) and without introducing other alterations of the polymer such as O-methylation, chain scission or loss of residual N-acetyl groups. Thiolated TMC with a DQ of 25% and a degree of thiolation of 5% showed rapid oxidation to yield disulfide crosslinked TMC at pH 7.4 while the thiolated polymer was rather stable at pH 4.0. Positively charged nanoparticles were made with fluorescently labeled ovalbumin and thiolated hyaluronic acid as cross-linker. Stability of these particles was confirmed in 0.8 M NaCl, in contrast to particles made from non-thiolated polymers which dissociated under these conditions.