Development and characterization of chitosan-based hydrogels as wound dressing materials

The purpose of the study was to develop hydrogel dressings with interpolymeric complexation using chitosan to enhance wound healing activity in excision wound model. Chitosan was cross-linked with polyvinyl alcohol (PVA), sodium alginate (SA) and Pluronic F68 at different ratios. The cross-linked hydrogel dressings were prepared with chitosan as the primary polymer using the freeze-thawing method. A biopsy punch was used to create wound onto the rat dorsum and the efficacy of the dressings was evaluated based on the time taken for complete healing of the wounds. The formulations exhibited optimum swelling degree within a range of 0.182 +/- 0.120 (H1) to 2.55 +/- 0.97 (A2) and gel fraction ranged from 7.73 +/- 3.21% (H2) to 46.36 +/- 1.89% (A2). Formulations S1 and S2 with chitosan and sodium alginate exhibited the highest values of water vapour transmission (55.61 +/- 1.89 g/cm(2)-day and 86.82 +/- 2.07 g/cm(2)-day respectively). High tensile strength was exhibited by formulation A1 and A2 (0.2352 +/- 0.058 N/mm(2) and 0.1236 +/- 0.026 N/mm(2)) with chitosan and PVA. Hydrogels with chitosan and Pluronic F68 exhibited a better rate of wound healing when compared to other formulations within a period of 15 days. The hydrogel dressings using the blend of chitosan and hydrophilic polymers substantiated to be a potential wound dressing.