表面富S^(2-)的CdS量子点的合成及其与甲硝唑的作用

Preparation of CdS Quantum Dots with Rich S^(2-) Surface and Study on Its Reaction with Metronidazole

在冰水浴条件下,用柠檬酸三钠和六偏磷酸钠为稳定剂,通过控制较低浓度的氯化镉溶液和硫化钠溶液缓慢反应,合成了荧光稳定性好、表面富硫的水溶性CdS量子点。利用荧光光谱、紫外-可见吸收光谱和共振光散射光谱研究了CdS量子点与甲硝唑相互作用的光谱行为,发现甲硝唑与CdS富硫表面的过量S2-的结合引起量子点的荧光猝灭效应,甲硝唑对CdS荧光量子点的荧光猝灭为静态猝灭,它们主要以静电引力结合。

Water soluble quantum dots(QD′s)of CdS with rich S2- surface and having good fluorescence stability,were prepared by the slow reaction of CdCl2and Na2S solution with controlled and low concentrations in an ice bath,using sodium citrate and sodium hexametaphosphate as stabilizing agents.Reaction between the CdS QD′s and metronidazole(MTDZ)was studied by fluorescence spectrometry,UV-VIS-absorption spectrometry and resonance scattering spectrometry.It was shown that quenching of fluoresence emission of the CdS QD′s was due to the binding of MTDZ with the excessive S2-on the surface of the CdS QD′s,and that the fluorescence quenching was attributed to static quenching,resulting mainly from combination by electrostatic force.