基于电场流分离技术的生物基质中氧化锌纳米颗粒的稳定性及其抗菌性能和细胞毒性机制研究

氧化锌纳米颗粒（ZnO NPs）具有优异的抗菌性能和光电催化活性，是目前研究最多、应用最广的纳米材料之一。随着ZnO NPs产品种类和数目的快速增加，其对人体健康和生态系统的潜在危害引发学术界的关注。ZnO NPs的抗菌性能和细胞毒性与其稳定性以及赋存形态分布特征密切相关。由于缺乏生物基质中ZnO NPs不同赋存形态分离分析的有效手段，其抗菌性能和细胞毒性机制尚不完全明确。本项目拟利用电场流分离技术分离度高、分离条件温和、适用范围广等特点，结合高选择性和高灵敏的检测系统，建立生物基质中离子态锌和颗粒态锌在线分离分析的方法；从ZnO NPs赋存形态分布变化角度，评估其在常用细菌培养基和细胞培养基中的稳定性；从分析细菌和细胞内外ZnO NPs赋存形态分布角度，研究模式细菌和模式细胞对其摄入过程，揭示其抗菌性能和细胞毒性机制，为科学评价ZnO NPs的抗菌性能和生物安全性提供重要依据。

Zinc oxide nanoparticles (ZnO NPs) are featured with excellent antibacterial activity and photoelectrocatalytic activity, making them as one of the most widely studied and applied nanomaterials. With the rapid increase in both kind and quantity of ZnO NPs-based products, the application of ZnO NPs has raised concern in scientific community over the safety of these materials to human health and the ecosystem. The antibacterial activity and toxicity of ZnO NPs have been found to be closely associated with their stability and speciation. However, the antibacterial activity and toxicity of ZnO NPs are still not fully elucidated mainly due to the lack of efficient separation and analysis methods of ZnO NPs and their products in biological matrix. In this proposal, we plan to (i) develop efficient and reliable methods to achieve separation and analysis of ionic and particulate zinc species using electrical field-flow fractionation hyphenated with highly selective and sensitive detectors; (ii) evaluate the stability of ZnO NPs in bacteria and cell culture media commonly used in view of the changes in kind and content of ZnO NPs and their products; (iii) study the model bacteria and model cells ingestion in term of distribution of ZnO NPs and their products within and outside of bacteria and cells to reveal mechanisms behind their antibacterial activity and toxicity, which will help lay the solid foundation for scientific assessment of antibacterial activity and biosecurity of ZnO NPs.