Enhancing the thermostability, UV shielding and antimicrobial activity of transparent chitosan film by carbon quantum dots containing N/P
writer：Lei Wang, Xiaodong Liu, Peng Qi, Jun Sun, Shengling Jiang, Hongfei Li, Xiaoyu Gu, Sheng Zhang
keywords：通過含有 N/P 的碳量子點增強透明殼聚糖薄膜的熱穩定性、紫外線屏蔽和抗菌活性
source：期刊
Issue time：2021年
The chitosan (CS) transparent film has attracted much attention in food and medicine packaging areas due to their biodegradability and good availability. A novel carbon quantum dots compound containing nitrogen and phosphorus (NP-CQDs) was obtained by reacting citric acids, with urea and phytic acids. The density of the film was increased, and the water vapor permeation was reduced by the presence of NP-CQDs. The introduction of 4 wt% NP-CQDs increased the water contact angle of the CS film from 79.2° to 105.8°. The shielding on UV-A and UV-B transmittance was increased with the NP-CQDs loading. The film containing 4 wt% NP-CQDs blocked more than 90.2% UV-A and 96.5% UV-B; however, it only blocked 26.8% visible light. It also exhibited better antibacterial activity to both E. coli and S. aureus than the control CS film. This work provided a feasible way to prepare multifunctional bio-safe film.
殼聚糖（CS）透明薄膜因其可生物降解性和良好的可用性而在食品和藥品包裝領域備受關注。通過檸檬酸、尿素和植酸反應獲得了一種新型的含氮和磷的碳量子點化合物（NP-CQDs）。由于 NP-CQDs 的存在，薄膜的密度增加，水蒸氣滲透率降低。4 wt% NP-CQDs 的引入使 CS 薄膜的水接觸角從 79.2° 增加到 105.8°。隨著 NP-CQDs 的加入，對 UV-A 和 UV-B 透射率的屏蔽增加。含有 4 wt% NP-CQDs 的薄膜阻擋了 90.2% 以上的 UV-A 和 96.5% 以上的 UV-B；然而，它只阻擋了 26.8% 的可見光。并且，也有較好的抗菌活性而?。大腸桿菌和S。aureus比對照 CS 片。該工作為制備多功能生物安全膜提供了一種可行的方法。