Cross-linked xanthan gum–starch hydrogels as promising materials for controlled drug delivery

Abstract

The work was intended to develop a novel acrylic acid grafted hydrogel by chemical crosslinking of xanthan gum and starch under microwave irradiation. The swelling capacity of hydrogel was found to be dependent upon pH. The maximum swelling capacity of hydrogel was recorded as 32.21 g/g under the optimized conditions. The swelling capacity of hydrogel was quite higher than most of the hydrogels containing xanthan gum mentioned in the literature. Various characterization techniques including FTIR, SEM, TGA and XRD confirmed successful synthesis of hydrogel with porous morphology and better thermal stability. Synthesized hydrogel was employed as an oral drug delivery vehicle. Releasing behavior of the hydrogels for the drugs aspirin and paracetamol was studied under specific physiological conditions. The drug release was significantly higher at pH 7.4 in comparison to acidic and neutral media. Synthesized hydrogel was found to be suitable for colon-specific drug delivery. Both aspirin and paracetamol followed non-Fickian diffusion mechanism at higher pH and Fickian mechanism at lower pH. Release profiles of both the drugs were best fitted in the first order model. Hydrogel was found to be non-cytotoxic to human fibroblast cells and biocompatible, with a low hemolytic ratio. Consequently results supported potential of this non-toxic, biofriendly and appropriately tailored polysaccharide based hydrogel to be used as drug delivery carrier for controlled and site-specific drug release.