Preparation, characterization, and protein loading properties of N ‐acyl chitosan nanoparticles

Various N ‐acyl chitosans with propionyl‐, hexanoyl‐, nonanoyl‐, lauroyl‐, pentadecanoyl‐, and stearoyl‐groups were synthesized and self‐aggregated N ‐acyl chitosan nanoparticles (CSNPs) were prepared by sonication. By the modification with N ‐acyl groups, CSNPs increased their hydrophobic character and changed its structural features to be more suitable as a delivery carrier. The mean diameters of bovine serum albumin (BSA)‐loaded N ‐acyl CSNPs ranged from 138 to 551 nm. Uniform particle size distribution of BSA‐loaded N ‐acyl CSNPs was observed. The protein loading efficiency of N ‐acyl CSNPs was about 94–95% with lower BSA concentration (0.1 mg/mL) and not significantly different with acyl chain length. With higher BSA concentration (1.0 mg/mL), however, the highest protein loading efficiency was observed with lauroyl and pentadecanoyl CSNPs. The results suggest that lauroyl and pentadecanoyl CSs are interesting candidates for protein delivery system. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012