Chitosan Hydrogel Beads: A Comparative Study with Glutaraldehyde, Epichlorohydrin and Genipin as Crosslinkers

By : Anupama Thakur , R. K. Wanchoo , Hardeep , S. K. Soni

Page No: 211-223

Abstract
The present study describes the synthesis of crosslinked chitosan (CS) hydrogel beads with chemical crosslinkers (glutaraldehyde and epichlorohydrin) and natural crosslinking reagent (genipin). Crosslinking was carried out for 24 h in case of glutaraldehyde and genipin and for 2 h in case of epichlorohydrin with constant stirring and heating at 30°C. Swelling study of crosslinked chitosan hydrogel beads was carried out in SIF (simulated intestinal fluid) and SGF (simulated gastric fluid) medium followed by diameter increase ratio (DIR). Increased swelling of hydrogels, under acidic conditions, was due to the protonation of primary amino groups on chitosan, as confirmed by FTIR analysis. Surface texture of hydrogel beads was analyzed by scanning electron microscopy (SEM), which revealed that crosslinked beads had smooth surface compared to non-crosslinked beads. Thermogravimetric analysis (TGA) suggested genipin crosslinked CS beads with highest thermal stability. The use of these hydrogels for drug release was studied using amoxicillin as the model drug. Release studies carried out in SGF showed the release mechanism to be anomalous in nature and suggested potential of these hydrogels in controlled drug delivery devices.

Authors :
Anupama Thakur, R. K. Wanchoo and Hardeep : Dr SS Bhatnagar University Institute of Chemical Engineering and Technology, Panjab University, Chandigarh -160 014, India
S. K. Soni : Department of Microbiology, Panjab University, Chandigarh -160 014, India