Potential of different salt forming agents on the formation of chitosan nanoparticles as carriers for protein drug delivery systems

Abstract

The effects of salt forming agents for chitosan on the potential for nanoparticle formation was investigated. The salt forms were prepared from the amino acid group, including glutamic and aspartic acids, and the alpha hydroxyl acid group, including lactic and glycolic acids. All types of chitosan salt could be used to prepare bovine serum albumin (BSA) loaded nanoparticles. The chitosan salts prepared from the amino acid group showed a higher salt formation ability as demonstrated using FTIR, hence a higher %encapsulation efficiency (%EE) and a reduction in zeta potential were obtained. The difference was due to the different organic acids used giving different polymer conformations and pH values in solution. Chitosan glutamate gave the highest salt formation ability and hence the highest %EE was obtained. The release of protein from all types of chitosan was similar and chitosan glutamate exhibited the highest release. Chitosan salt is therefore a material of choice for protein-loaded nanoparticles and the characteristics of nanoparticles can be readily modulated by different types of salt form.