Preparation, characterization and protein loading of hexanoyl-modified chitosan nanoparticles.

Hexanoyl chitosan was synthesized through a coupling reaction between chitosan and hexanoic anhydride. Proton nuclear magnetic resonance (1HNMR) and fourier-transform infrared (FTIR) spectroscopy studies showed the formation of hexanoyl chitosan. The nanoparticles of hexanoyl chitosan were prepared through ionotropic gelation with tripolyphosphate (TPP) followed by sonication. The hexanoyl chitosan-TPP nanoparticles exhibited uniform spherical shape with smooth surface as observed by atomic force microscopy and transmission electron microscopy. The particle size of nanoparticles was between 54.1 to 724 nm with a mean diameter of 324 nm. At 0.2, 0.4, and 0.6 mg/mL bovine serum albumin initial concentration, the encapsulation efficiency and loading capacity of hexanoyl-chitosan-TPP nanoparticles were 58.2, 44.5, and 28.1%, and 14.1, 23.4, and 30.3%, respectively.