Enhancing Physiochemical Properties of Chitosan Films Through Photo-crosslinking by Riboflavin

This study aimed to improve the physicochemical properties of chitosan (CS) film by riboflavin (RF)-induced cross-linking under ultraviolet (UV) light for different times (0, 2, 4, 6 h). It was found that the water vapor resistance, tensile strength, optical property, and thermal stability of the film were significantly enhanced under RF-induced photo-crosslinking, especially when illuminated for 6 h. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) verified the molecular bonding of CS and RF, as well as scanning electron microscope (SEM) showed a tighter and more uniform film structure was formed through UV crosslinking. Thus, the CS-RF films have the potential to replace petrochemical materials as a novel type of environmentally friendly packaging material.