Preparation and characteristics of antibacterial chitosan films modified with N-halamine for biomedical application

Several hydantoin derivatives and their N-halamine analogues were examined by spectroscopic methods (IR, ¹H-NMR, ¹³C-NMR), elemental analysis (content of C, H, N), thermogravimetry (TGA), antibacterial tests and experiments of stability in aqueous solution. This research allowed the structural, thermal and antibacterial characteristics of obtained compounds. It was found, the thermal stability of hydantoins depends on their chemical structure and decreases when N-halamine moieties were introduced. In next step, synthesized biocides were added to the chitosan films. The antibacterial properties of received films were proved. It was found that after modification, the thermal stability of CS films decreases in most cases. The surface properties of obtained chitosan films before and after UV irradiation were investigated by means of contact angle measurements allowing the calculation of surface free energy. The chemical and structural changes during UV irradiation were studied by FTIR spectroscopy and SEM microscopy. The results indicated that the introduction of biocides to the CS material contribute to the photooxidation process. The degradation mechanism of obtained materials was proposed. The materials studied in this work may be used in various biomedical applications due to their confirmed biological activity.