A Novel Topical Biocompatible Tissue Adhesive Based on Chitosan-modified Urethane Pre-polymer

A novel tissue adhesive composed of urethane pre-polymer and chitosan gel was synthesized in a two-step procedure. The first step of the procedure was carried out under nitrogen atmosphere at 60 degrees C and 24 h and the final formulation was prepared using a urethane pre-polymer and 2% chitosan gel. The presence and quantity of NCO groups in the adhesive were determined using FTIR spectroscopy and titration methods. The presence of the urethane band and NCO free groups in the adhesive were confirmed at 1514 cm(-1) and 2261 cm(-1), respectively and the quantity of NCO free groups was calculated as 21%. The molecular weight of urethane pre-polymer in the adhesive was measured 2444.7 g/mol using GPC. The relative peel resistance of the adhesive bonds between flexible adherents was 15.1 N for urethane pre-polymer and 14.6 N for the final formulation of tissue adhesive. Chitosan gel was used in this tissue adhesive to increase its biocompatibility. The structure of the synthesized adhesive which exhibited a porous structure due to the presence of chitosan gel was illustrated using SEM technique. The surface energy of the adhesive which was lower than its values for gelatin, skin and blood was determined by contract angle measurment as 33.65 mN/m. Cytotoxicity of the tissue adhesive was determined on growth and viability of various cells, using CaCO(2), T47D, HT29 and NIH3T3 cell lines which showed adhesive's non-cytotoxic nature. The skin irritation test, carried out according to ISO 10993-10, suggested that the compound is non-irritant.