Formation of Biocompatible Nanoparticles via the Self-Assembly of Chitosan and Modified Lecithin

摘要

The formation of biocompatible nanoparticles via the self-assembly of chitosan (CHI) and modified lecithin (ML) was studied. Stable nanoparticles in the size range of 123 to 350 nm were formed at over a wide mo- lar mixing ratios of CHI/ML, solutions (amino group/phosphate group) (NH_3~+/PO_3~- ) and total polyelectrolyte (PE) concentrations (0.1 to I wt%) except at intermediate molar ratios when the surface charge was close to neutrality. Zeta-potentials of the nanoparticles were found to be independent of the total PE concentrations. Nanoparticles exhibited excellent stability at over an extended pH (pHs 3 to 6) and ionic strength range {< 500 mM NaCl concen-tration). The particle size and zeta-potential of the nanoparticles increased with the molecular weight of CHL. Trans-mission electron microscopy suggested that nanopartides were generally spherical in shape with CHI constituting the exterior of its surface at high molar mixing ratios. Dextran-fluorcscein isothiocyanate, bovine serum albumin, and Coomassie brilliant blue as models of nonionic, positively and negatively charged compounds were encapsu-lated within the nanoparticles at between 8.7% and 62.7% efficiency. The ability of the nanoparticle suspensions to he converted to lyophilized powder or concentrated suspension was also demonstrated.