Fabrication of Dual Photodynamic Enhanced Antimicrobial CDs@ZIF‐8/Polycaprolactone/Ethyl Cellulose Nanofibrous Films for Fruit Preservation
Yongrui Ti, Ziqiang Qin, Xiaohong Guo, Zhenhua Wu, Qi Jiang, Beihua Dong, Olaniyi Amos Fawole, Di Wu, Su Chen, Li X, Kunsong Chen
Abstract
Abstract Carbon dots (CDs) have elicited attention in photodynamic antimicrobial applications, but their susceptibility to aggregation limits their effectiveness. Herein, CDs@ZIF‐8 nanocomposites are synthesized. The results reveal that they have superior dual photodynamic enhanced antimicrobial properties, specifically 7.63 log 10 CFU mL −1 (lg) elimination for Escherichia coli (only 3.12 lg with CDs and 4.18 lg with ZIF‐8) and 7.27 lg elimination for Staphylococcus aureus (only 4.17 lg with CDs and 2.94 lg with ZIF‐8). Optoelectronic property analysis and density functional theory calculations show that the enhanced photodynamic antimicrobial properties of CDs@ZIF‐8 can be attributed to their narrow bandgap and higher binding affinity for O 2 , which facilitates the photo‐generated e − –h + pairs separation and promotes the generation of 1 O 2 and •O 2 − . Furthermore, the CDs@ZIF‐8/polycaprolactone/ethyl cellulose nanofibrous films are prepared by microfluidic‐blow‐spinning, which have prominent antimicrobial properties and extend the shelf life of strawberries from 6 to 12 d. Overall, this study provides a novel idea for designing synergistically enhanced photodynamic antimicrobial materials and photodynamic preservation of perishable fruits.