微量热法研究不同形貌的ZnO和Ag/ZnO纳米复合材料的抗菌性能及机制

As a typical nano metal oxide antimicrobial material, ZnO nanomaterial have attracted more and more attention due to their chemical stability, inherent safety and durability. Presently，enhancing the antibacterial activity of ZnO nanomaterial have became an urgent problem to the researchers. Meanwhile, Ag has been known to be a good antimicrobial agent because it shows strong antibacterial effects on many pathogenic bacteria, and is being used in many forms for the treatment of infectious diseases. This project is based on morphology-controlled synthesis of ZnO nanomaterial, and intended to explore an available process to prepare Ag/ZnO nanocomposite with good antibacterial activity. The antibacterial activity of the ZnO nanomaterial and Ag/ZnO nanocomposite on Escherichia coli, Staphylococcus aureus, mould fungi will be detected by microcamlorimetry, respectively. The antibacterial process of ZnO nanomaterial and Ag/ZnO nanocomposite will be monitored on-line by microcamlorimetry. In order to get an effective way to improve the antibacterial activity of ZnO nanomaterial and Ag/ZnO nanocomposite, we will investigate the effects of the light, antimicrobial agents' morphology on the antibacterial efficiency, and establish the relationship between environment - structure - antibacterial activity. Combining with other methods such as TEM, SEM, ICP, the antibacterial mechanism of the nano metal oxide antimicrobial agents will be predicted, which can help us to develop the antimicrobial agent with high antibacterial activity and lower cost.

ZnO纳米材料是一种典型的纳米金属氧化物抗菌材料，因其化学性质稳定、对生物无毒、来源丰富而成为抗菌剂的研究热点。目前，如何进一步提高ZnO纳米材料的抗菌性能是该体系急需解决的问题之一。同时，贵金属Ag由于其自身优异的抗菌性能也倍受研究者的青睐。因此，本项目以合成不同形貌的ZnO纳米材料为基础，发展可控制备具有优良抗菌性能的Ag/ZnO纳米复合材料的方法与技术。着重利用微量热法分别实时在线监测不同形貌的ZnO纳米材料和Ag/ZnO纳米复合材料对大肠杆菌、金黄色葡萄球菌、霉菌的抗菌过程，定量检测其抗菌性能，系统研究抗菌性能与光照、形貌的关联规律，建立环境-结构-抗菌性三者之间的关系，探索提高ZnO纳米材料抗菌活性的有效途径。同时结合其它表征手段，深入探索纳米金属氧化物的抗菌机制，为设计和开发高效廉价的抗菌剂奠定坚实理论基础和实验依据。

本项目以合成不同形貌的ZnO 纳米材料为基础，发展大规模可控制备具有优良抗菌性能的Ag/ZnO 纳米复合材料的方法与技术为目的，着重利用微量热法监测不同形貌的ZnO 纳米材料和Ag/ZnO 纳米复合材料对细菌的抗菌过程，为设计和开发高效廉价的抗菌剂奠定坚实理论基础和实验依据。通过系统的研究，积累了丰富数据，取得了一些重要研究成果：1）成功开发了大规模制备形貌可控的ZnO 纳米材料的方法，纳米结构主要包括：纳米线、纳米片和纳米球；2）系统考察了不同形貌ZnO 纳米结构的抗菌性能，发现ZnO 纳米线具有最优的抗菌性能；3）开发了利用模板法制备尺寸和形貌可控的金属纳米粒子，该方法具有普适性,适合Ag、Au、Pt、AgAu 双金属等纳米粒子的可控制备；4）以Ag/ZnO 为模型催化剂，系统考察了不同形貌的ZnO 纳米材料负载Ag 的抗菌性能，发现Ag/ZnO 纳米线复合材料具有最优的抗菌作性能，结合微量热结果和电镜表征结果构建了ZnO 纳米材料和Ag/ZnO 纳米复合材料的结构与抗菌性能的关系。