Film production and characterization from natural polymers for biomedical applications

In this study, the synthesis of silk protein sericin (Ser) added biomedical films containing different natural polymers, which have the potential to be used as a wound dressing, was studied. Smoke tree (Cotinus coggygria) leaf extract, which has wound healing properties, and AgNO3, were added to the polymer mixtures, and the films produced by the solvent casting method were exposed to UV-C light, resulting in simultaneous green synthesis of silver nanoparticles (AgNP). In the first stage of formulation optimization studies of biomedical films, carboxylmethyl cellulose (CMC), gelatin (JLT), tara gum (TG) polymers and glycerol (GLY) as plasticizer were used. In addition, different amounts of silver nitrate (0,1 M AgNO3) (0, 1, 3 mL) and UV-C irradiation durations (0, 2, 4 hours) were tested. Sericin added films were formed, while CMC and xanthan gum (KG) were used as polymers, glycerol was added as a plasticizer. In the last step, the selected sericin-containing film was immersed in CuCl2 solutions of different concentrations and cross-linking was carried out. The synthesized biomedical films were characterized by measurements of their thickness, opacity, percent elongation and tensile strength, water vapor permeability, solubility, moisture holding capacity, swelling ability. Furthermore, they were analyzed by scanning SEM, TGA, FTIR, by determination of total phenolic content, antioxidant and antimicrobial activity, protein release and cytotoxicity analyses. As a conclusion, these durable, biocompatible, antioxidant and antimicrobial films, synthesized from natural polymers, have been shown to have the potential to be used as wound dressings. Keywords: Biomedical film, Silk sericin, Smoke tree, Silver nanoparticle, Green synthesis.