多功能纳米光敏剂NaYF4:Yb,Tm@NaGdF4:Yb@PDA/PEI-MnO2的制备及抗菌性能

Preparation and antibacterial performance of multifunctional nanophotosensitizers NaYF4:Yb,Tm@NaGdF4:Yb@PDA/PEI-MnO2

摘要:

采用反相微乳液法制备了含有上转换纳米粒子NaYF4:Yb,Tm@NaGdF4:Yb、聚多巴胺、聚乙烯亚胺和MnO2的多功能纳米光敏剂（UPM），借助TEM、FTIR、XPS、UV-Vis、PL和DLS表征了产物的形貌、化学组成、光学性质和粒径分布，测试了UPM的活性氧物种产生能力、对盐酸四环素(TC)的负载与释放性能，研究了负载TC的光敏剂（UPM/TC）在近红外（NIR）光照下的抗菌性能。结果表明，UPM具有类过氧化氢酶活性，在H2O2存在和NIR光照下产生羟基自由基与单线态氧。UPM对TC载药量为22.6%，体外释放具有pH响应特征。在功率密度 1.2 W/cm2的980 nm NIR光照射10 min后，质量浓度为0.8 g/L的UPM/TC对大肠杆菌的杀菌率达到99.7%，抗菌效果优于TC或UPM，呈现出光动力-抗生素协同抗菌效应。

Abstract:

Multifunctional nanophotosensitizers (UPM) composing of upconversion nanoparticles NaYF4:Yb,Tm@NaGdF4:Yb, polydopamine, polyethyleneimine and MnO2 were prepared by reverse microemulsion method. The morphology, chemical composition, optical properties and size distribution of the obtained products were characterized by TEM, FTIR, UV-Vis, PL and DLS. Then, the reactive oxygen species generation ability and the loading and release of tetracycline hydrochloride (TC) from UPM were measured, and the antibacterial performance of TC-loaded nanophotosensitizers (UPM/TC) under near-infrared (NIR) light irradiation was investigated. The results showed that the nanophotosensitizers showed catalase-like activity and the capacity of producing hydroxyl radical and singlet oxygen in presence of H2O2 as exposed to NIR light. The loading capacity of TC in UPM was 22.6%, and the in vitro release of TC was pH-sensitive. After exposure to 980 nm NIR light (1.2 W/cm2) for 10 min , UPM/TC at a mass concentration of 0.8 g/L exhibited 99.7% bacterial inactivation to E. coli and better antibacterial performance than free TC or UPM by virtue of the synergistic effect of photodynamic and antibiotic sterilization.