本文在温和条件下成功制备出PDA@CaCO3/SiO2复合纳米光敏剂。并用X射线衍射、傅里叶变换红外光谱、场发射扫描电子显微镜、Brunauer- Emmett-Teller对样品进行一系列表征。对比了PDA@CaCO3/SiO2复合纳米光敏剂和CaCO3/SiO2对大肠杆菌（Escherichia coli，E. coli）的抑菌效果。实验结果表明，PDA@CaCO3/SiO2复合抗菌剂具备卓越的光热转换性能，并在8 min内实现温度快速上升至47.5 ℃。经1.2 W/cm2功率的近红外光照8 min后，CaCO3@SiO2和PDA@CaCO3/SiO2对大肠杆菌的杀菌率分别达到了90.40%和97.34%。经过3次重复实验后，PDA@CaCO3/SiO2复合抗菌剂抑菌率仍可达90%以上。含有PDA@CaCO3/SiO2复合抗菌剂的保鲜膜抑菌试验表明，PDA@CaCO3/SiO2复合抗菌剂可以有效抑制水果表面的大肠杆菌，水果经贮藏4天后，抑菌率仍为97%。PDA@CaCO3/SiO2复合抗菌剂生物相容性好。该研究证明了PDA@CaCO3/SiO2复合抗菌剂对大肠杆菌的抑菌性能，为水果中可降解光热抗菌剂的研发提供理论支持。

In this work, PDA@CaCO3/SiO2 composite nano photosensitizer was successfully prepared under mild conditions. The samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and Brunauer Emmett Teller analysis, etc. The bacteriostatic effects of PDA@CaCO3/SiO2 composite nano photosensitizer and CaCO3/SiO2 on Escherichia coli (E. coli) were compared. The experimental results showed that PDA@CaCO3/SiO2 composite antibacterial agent had excellent photothermal conversion performance, and the temperature rapidly rised to 47.5 ℃ within 8 min. After 8 min of NIR irradiation with 1.2 W/cm2 power, the bactericidal effects of CaCO3@SiO2 and PDA@CaCO3/SiO2 on E. coli reached 90.40% and 97.34% respectively. The antibacterial rate of PDA@CaCO3/SiO2 compound antibacterial agent could still reach more than 90% after three repeated experiments. The antibacterial test of plastic wrap containing PDA@CaCO3/SiO2 showed that PDA@CaCO3/SiO2 could effectively inhibit Escherichia coli on the surface of fruits, and the antibacterial rate was 97% after 4 days of storage. PDA@CaCO3/SiO2 composite antibacterial agent has good biocompatibility. This study demonstrated the antibacterial performance of PDA@CaCO3/SiO2 composite antibacterial agent on Escherichia coli, and provided theoretical support for the research and development of biodegradable photothermal antibacterial agents in fruits.

山东省高等学校海洋食品药品资源开发新技术研发中心科研开放专项资金项目(SDSY20240007)；威海市医用调理功能食品加工技术重点实验室2024年度科研开放专项资金项目(WHYY20240007)