Preparation of in situ cross-linked N-maleoyl chitosan-oxidized sodium alginate hydrogels for drug delivery applications

Abstract

AIM: This study was aimed to prepare in situ cross-linked N-maleoyl chitosan – oxidised sodium alginate (MCS – OSA) hydrogel loaded with metronidazole (MTZ) for drug delivery applications. METHODS: The hydrogel was prepared by in situ cross-linking via Schiff base reaction between amine (-NH2) groups from MCS and aldehyde (-CHO) groups from OSA at the different ratio, and the MTZ was loaded into the hydrogels along with the gelatin processes. RESULTS: The highest drug entrapment efficiency (DEE) was exhibited by MTZ-H3 (5: 5) with DEE of 99.20% and a gel fraction of 97.52%. FTIR results revealed that Schiff base reaction was occurred by the absorption peak of –C = N-groups at 1628 cm-1 and indicated that there is insignificant alteration at different ratio of MCS and OSA. The best sustained of in vitro release profiles of MTZ was shown by MTZ-H3, which is 74.92% and 75.65% at pH 1.2 and 7.4 for 12 h of release, respectively. CONCLUSION: The optimised ratio between MCS and OSA to prepare in situ cross-linked hydrogels were found to be 5:5 according to the results of DEE and in vitro drug release profiles of MTZ and the MTZ loaded MCS-OSA hydrogels have a great potential which can be applied in biomedical applications.