Influence of chitosan coating on the liposomal surface on physicochemical properties and the release profile of nanocarrier systems.

Chitosan-coated nanoliposomes containing etofenprox or alpha-cypermethrin prepared by ultrasonic homogenization maintained a size distribution in the nanometre range. Nanoliposomes were constructed using different types and concentrations of chitosan to regulate the mean size and surface charge. As the chitosan concentration (0.1-0.5%, w/v) and the degree of deacetylation increased, surface charge also increased. The encapsulation efficiency and release profile were measured by gas chromatography. Encapsulation efficiency decreased slightly as chitosan concentration increased (0.1-0.5%, w/v). As the intrinsic surface charge or concentration of the coating material increased, the release period of the entrapped core material was extended (chitosans A and B; 0.1 and 0.3%, w/v). The results indicate that diverse preparation conditions could affect the physicochemical properties and release profile of the resulting nanocarrier systems.