Abstract: Self-assembled nanomicelles of N-cholesterol succinyl O-carboxymethyl chitosan(CCMC) were prepared by probe sonication method. The amphiphilic property and the critical micelle concentration(cmc) of CCMC were determined by fluorescence probe technique; the morphology and the size of CCMC self-assembled nanomicelles were analyzed by transmission electron microscopy(TEM) and the dynamic laser light scattering(LLS). Paclitaxel(PTX), being used as model drug, was entrapped into CCMC self-assembled nanomicelles by dialysis method. The drug loading and release properties were estimated by high performance liquid chromatography(HPLC). The results show that CCMC was an amphiphilic polymer and formed regularly spherical nanomicelles(mean diameter=198.4 nm) in aqueous medium by self-assembly, and the cmc value of CCMC was 0.018 mg/mL. PTX-loading CCMC self-assembled nanomicelles were successfully prepared, with drug loading content as high as 34.9%, and their mean diameter increased with increasing the drug loading content. PTX continuously released from CCMC self-assembled nanomicelles in the release media of phosphate buffered saline(PBS) solutions, and its release was sensitive to the pH of the release media.

Key words: N-Cholesterol succinyl O-carboxylmethyl chitosan, Self-assembled nanomicelle, Drug carrier