Abstract
This study utilized electrospinning to create in situ composite layers of polyvinyl alcohol (PVA) and polylactic acid (PLA) films. Through molecular grafting, the antimicrobial photoinitiator 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BD) was anchored to the PVA surface, followed by chlorogenic acid (CA) attachment, forming a composite film with rechargeable photodynamic properties. Scanning electron microscopy showed that the nanofiber structure remained intact post-grafting, while nuclear magnetic resonance confirmed successful bonding of BD and CA with PVA. The composite films exhibited enhanced hydrophobicity, with the PLA/PVA-BDCA film achieving a 44 % increase in contact angle. Antibacterial tests showed significant efficacy in both light and dark conditions, with light exposure doubling the antibacterial rate. The PLA/PVA-BDCA film reduced colony counts by about 3 log units and generated the highest free radical levels (approx. 400 μg/g), over twice that of other films. Ultraviolet irradiation enabled regeneration of its antibacterial function up to five cycles, supporting its sustainable use.