Development of new gallic acid loaded films for wound dressings: In vitro and in vivo evaluations

Abstract

Wounds that cannot be treated and become chronic remain among the most challenging health problems with financial burdens worldwide. Herein, gallic acid (GA) loaded polymeric films were developed using HPMC (Hydroxypropyl methylcellulose) or sodium alginate as the main polymer, and characterizations were examined. Weights were found between 681.25 f 29.77 and 329.25 f 4.21 mg and the thickness was in between 1.40 f 0.09 and 0.70 f 0.01 mm range. pH values were quite close to neutral. Moisture uptake and loss results were in harmony with plasticizer concentration that was also observed with texture profile analysis such as elongation at break 74.45 f 2.70 % which corresponds to tensile strength 0.034 f 0.005 N/mm2 for H4 that is suitable for wound application. Swelling of the films was found higher with sodium alginate-containing formulations compared to HPMC-based films due to lower molecular weight. In vitro release study exhibited that the release of GA from both HPMC and sodium alginate-based films reached 100 % in 3 h. Ex vivo permeation and penetration were found to be low which is preferred for wound treatment. In vitro biological assays were assessed in terms of in vitro antioxidant capacity, in vitro wound healing assays, and in vitro anti-inflammatory evaluations. H4 indicated the highest free radical scavenging activity and the highest dose-dependent wound healing potential with 1 mg/ml (96 % on the 24th hour). Finally, in vivo studies were performed on mice with control, market product, blank, and GA-loaded films and histopathological assessment. All findings revealed that the film containing GA, HPMC, PVP (polyvinylpyrrolidone), and propylene glycol is an outstanding alternative wound therapy.