Calendula flower extract loaded collagen film exhibits superior wound healing potential: Preparation, evaluation, in-vitro &in-vivo wound healing study

The present study was aimed to prepare Calendula flower extract loaded collagen film as a safe and effective wound dressing. Collagen film was prepared by solvent casting method and characterized for physicochemical properties like water absorption capacity, total phenolic content, total flavonoid content, antioxidant activity, infrared spectra, biodegradation, moisture content, differential scanning calorimetry, and sterility. The triple helical structure of collagen in the formulation was confirmed by gel electrophoresis and atomic force microscopy study. The safety and efficacy of developed formulation were investigated by in-vitro cell culture experiments including MTT assay, scratch assay on 3T3 Swiss albino cell line, In-vitro hemolysis study and In-vivo wound healing animal study on Wistar rats. In-vitro cell cytotoxicity test showed that the developed film was non-cytotoxic. In-vivo animal study on Wistar rats showed rapid wound healing compared to non-treated and placebo-treated group. The rate of wound contraction was significantly (p