Gum ghatti-based biodegradable and conductive carriers for colon-specific drug delivery

Conductive superabsorbent hydrogels based on gum ghatti (Gg)/methacrylic acid (MAA)/aniline (ANI) were synthesized by gamma radiations initiated by two-step aqueous polymerization. A cross-linking agent N,N′-methylene-bis-acrylamide was used in the polymerization process, and MAA was graft-copolymerized onto Gg by γ-rays. Influence of preparative conditions (absorbed dose, monomers, solvent, and cross-linker concentrations) on the swelling behavior of cross-linked polymer systems has been investigated. Synthesized superabsorbent hydrogels were characterized using thermogravimetric analysis and swelling studies. In biodegradation study of synthesized hydrogels by composting soil method, Gg-cl-poly(MAA-ipn-ANI) showed better degradation efficiency in comparison to Gg-cl-poly(MAA). Synthesized hydrogels were loaded with amoxicillin trihydrate as a model drug to investigate the release behavior of hydrogels at different pH media. Kinetics studies revealed that synthesized hydrogels exhibit a Fickian diffusion behavior at pH 2.4 and 7.2. However, at pH 9.2, a non-Fickian diffusion behavior was observed which make them very suitable for colon-specific drug delivery applications.