The effect of Chitosan Concentration Change and the Effect of Chitosan Solution pH Change on the Structural Properties of Chitosan Nanoparticles Made by Ionic Gelation Method

In this study, chitosan nanoparticles were prepared by ionic gelation method. Three concentrations of 2 mg/ml, 4 mg/ml and 10 mg/ml were prepared to evaluate the effect of chitosan concentration on the size of chitosan nanoparticles. The results showed that with increasing chitosan concentration, the particle size of the chitosan nanoparticles becomes larger. In the best conditions, particles with average size of 90 nm was obtained. In order to evaluate the effect of chitosan solution pH change on the size of chitosan nanoparticles, the effect of two pHs, 5.0 and 8.4 on all three concentrations of chitosan solution was investigated. The results showed that with increasing chitosan solution pH, the particle size of the chitosan nanoparticles becomes smaller. In the best conditions, in pH equal to 8.4, particles with average size of 90 nm for concentration of 2 mg/ml, average size of 106 nm for concentration of 4 mg/ml, average size of 124 nm for concentration of 10 mg/ml were obtained. In these two examinations, scanning electron microscope images show the chitosan nanoparticle’s sticking and sponge. FTIR spectra were recorded for the specimens and the formation of nanoparticles proved to be due to the disappearance of a peak in the spectrum of crossing and the creation of two new peaks in the spectrum due to the ionic crosslinking between phosphoric ions and amine groups ions.