Background: Microwave assisted grafting of natural materials enables their use for specific drug delivery application. Microwave assisted reactions have numerous advantages like rapid reactions, improved yields, high purity products, simple, safe, efficient and ease of scale up.
Methods: In the present study graft copolymers of n-vinyl-2-pyrrolidone and locust bean gum were prepared by microwave assisted graft copolymerization using ceric ammonium nitrate as redox initiator. The grafted procedure was optimized in terms of irradiation time, amount of initiator and n-vinyl-2- pyrrolidone by using constant amount of the gum. Characterization of the grafted gum was carried out by FTIR, XRD, DSC, elemental analysis and swelling studies. In vitro release behaviour of graft copolymer was comparatively evaluated with ungrafted gum by formulating the matrix tablets for colon specific delivery of budesonide.
Results: Results of FTIR, XRD, DSC confirmed grafting of the gum. Elemental analysis of pure gum showed negligible amount of nitrogen in it (0.942%) but grafted gum showed good quantity of nitrogen content (2.48%), which confirmed the successful grafting of locust bean gum. The grafted gum was employed to prepare controlled release tablets of budesonide which were evaluated for colon specific drug delivery.
Conclusion: Microwave assisted grafting of locust gum was performed successfully. The in vitro drug release revealed that the grafted gum has application for the development of colonic drug delivery system.
Keywords: Budesonide, ceric ammoninum nitrate, colon delivery, locust bean gum, n-vinyl-2-pyrrolidone grafted locust bean gum, n-vinyl-2-pyrrolidone.