Modeling and Comparison of Different Simulations for Release of Amoxicillin from Chitosan Hydrogels

Abstract

In this research work, different devices made of glutaraldehyde cross-linked chitosan hydrogels loaded by amoxicillin, have been prepared using freeze-drying method. Effects of system parameters such as cross-linker concentration, pH, and gel structure on the morphology and release behavior of devices have been investigated using standard methods. Morphological studies were performed using SEM instrument and controlled releases are followed via spectrophotometeric method. Reaction of glutaraldehyde with chitosan has been studied using FTIR instrument. SEM micrographs have shown that with increasing cross-linker percentage in hydrogel, pore sizes increased where pore size distribution decreased. Considering that biocompatibility and drug release rate of the device can be affected by presence of cross-linker, effects of cross-linker concentration on drug release rate and biocompatibility of the device have been investigated and its appropriate concentration have been determined. Experimental release data were analyzed using Higuchi model originally developed for porous devices and swellable polymer model presented for porous swellable systems. Comparison of experimental results and model predictions shows that the Higuchi's model would be valid for systems with molar ratio (cross-linker-chitosan amine groups) less than 0.18, whereas the swellable polymer model could better predict behavior of systems with molar ratio more than 0.18.