Biodegradable photosensitive antimicrobial hydrogel film based on curcumin-carbon dots for raw meat preservation

Biodegradable photodynamic antimicrobial hydrogel films have gained significant attention for food preservation. Konjac glucomannan (KGM) based hydrogels offer commendable biocompatibility and biodegradability but exhibit low antimicrobial activity. While curcumin (Cur) is widely incorporated into biodegradable antimicrobial packaging, it often compromises transparency and shortens the functional lifespan of hydrogel films. In this study, we report a biodegradable photosensitive film based on KGM, polyvinyl alcohol (PVA), D-sorbitol and Curcumin‑carbon dots (Cur-CDs). The water penetrating in the film show the Fick diffusion behavior, and biodegraded 27.90 % within 4 weeks. Cur-CDs enhanced hydrogen bonding between KGM and PVA, resulting in a smoother film surface, a 17.80° reduction in water contact angle, and a 24.91 % increase in transparency. Besides, the light stability of Cur-CDs in film was significantly enhanced. Accordingly, 1.74 × 10⁴ CFU microbial colony was photodynamic eliminated when applied on pork preservation, showing the promising potential application in food preservation.