Investigating the effect of chitosan’s degree of deacetylation on size of the nanoparticle

Abstract

Chitosan (CS) is a naturalcationic polysaccharide obtained by deacetylation of chitin, a biopolymer found mainly in the exoskeleton of crab, shrimp shells, etc. The chitosan degree of deacetylation (DD) is an important factor which determines some of the physiochemical and biological properties of chitosan. The present study focuses on evaluating the effect of chitosan DD on nanoparticle size by using three different DD of chitosan, i.e., 85%, 90% and 93%. Chitosan nanoparticles were prepared by ionic gelation method using sodium tripolyphosphate (TPP) as crosslinker. The particle size and polydispersity index (PDI) was studied using Dynamic Light Scattering (DLS) and was further characterized by Fourier Transform Infrared spectroscopy (FTIR) to confirm the interactions between the ammonium groups of CS and tripolyphosphoric groups of TPP in the prepared nanoparticles. The results demonstrated that nanoparticles prepared using 85% DD chitosan had an average particle size of 100.2 ± 0.5 nm.