Effect of glutaraldehyde as fixative in modulating swelling profile on gelatin-chitosan composites

Objectives: Fabrication of cross-linked biopolymer based composites (viz., gelatin and chitosan) and role of cross-linking on swelling. ls & Methods: Gelatin (Merck, India) gel is prepared with 10% (w/v) of the polymer. Likewise, Chitosan (Marine Chemicals, India) gels are prepared with 1% (w/v) chitosan in 2% (v/v) lactic acid solution and composite gels are prepared blending with 5% (w/v) gelatin and 1% (w/v) of chitosan. All these polymer solutions are cross-linked with varied concentrations of glutaraldehyde solution. After fabricating these cross-linked gels, they are subjected to swelling test in order to determine the swelling behavior with respect to different concentrations of glutaraldehyde (Hi Media, India). The statistical significance of the results with and without cross-linking were evaluated and analyzed. Results: In earlier reports, author demonstrated that the temperature has direct influence over cross-linking. In recent study, the effects of cross-linking on swelling of polymer composites at varied proportions of cross linkers were evaluated. Results showed that, composites which has higher degree of cross-linking, swelled less owing to relatively compact gel architecture. Conclusion: Cross-linked and uncross-linked gel composites were analyzed and result suggests that, composites when cross-linked provides better regulation on swelling profile which eventually leads to modulate swelling dependent transport of bioactive molecules. Therefore the cross-linked gels showed the promising results.