Incorporation of lysozyme-rectorite composites into chitosan films for antibacterial properties enhancement

The demand for designing antibacterial materials was quite substantial in packing and biomedical materials fields. Chitosan had a wide utilization to satisfy this demand. In this study, by incorporating lysozyme (LY) - rectorite (REC) into chitosan films, the ultimately obtained hybrid films can own the enhanced antibacterial properties and still remains good mechanical properties. Scanning electron microscopy (SEM) images revealed that LY and REC could be homogeneously distributed in the CS films. X-ray photoelectron spectroscopy (XPS) and Energy-dispersive X-ray analysis (EDX) results verified that the LY-REC incorporation process was successful. Small angle X-ray diffraction (SAXRD) and Fourier transform infrared (FT-IR) spectra revealed that some intercalation reactions occurred between CS chains and REC. The hydrophobic properties of the CS films were increased by the addition of LY and REC, determined by water contact angle measurement. In comparison with CS films, the mechanical properties of the composite films after adding LY-REC were reduced by 27.58%, but still maintained high tensile strength. Besides, the antibacterial properties of the films could be enhanced by introducing LY-REC. This method exhibited great application value in the food packaging fields. (C) 2017 Elsevier B.V. All rights reserved.