半胱胺修饰的CdS纳米粒子荧光猝灭法测定锰离子

Fluorescence Quenching Method for the Determination of Manganese Ion with Cysteamine-capped-CdS Nanoparticles

常温下在水溶液中制备了半胱胺修饰的CdS纳米溶胶，并用原子力和扫描电子显微镜、傅立叶变换红外、紫外．可见分光光度法、荧光分光光度法测试技术对其进行了表征。以修饰的纳米粒子为荧光探针，建立了荧光猝灭定量检测锰离子的新方法。考察了不同缓冲体系、缓冲液浓度及缓冲液pH值、反应时间、纳米粒子浓度等多种因素的影响。在最佳实验条件下，测定锰离子的线性区间为0．05340～77．62mg／L，检出限为0．01678mg／L。方法经济、简单、快速、灵敏度高、检出限比较低、检测范围宽。

Water-soluble Cysteamine-capped-CdS nanoparticles were prepared in aqueous solution at room temperature, and characterized by atomic force microscopy, scanning electron microscopy, Fourier transform infrared spectrometry, Ultraviolet-visible spectrometry, and spectrofluorimetry, respectively. A new approach was proposed for the sensitive determination of manganese ion with nanoparticles as the fluorescence probe. Different influencing factors were studied, including the concentration and pH of buffer, reaction time, and concentration of the nanoparticles. Under the optimum conditions, the response was linearly proportional to the concentration of manganese（ Ⅱ） ion in a range of 0. 053 40 mg/L to 77.62 mg/L. The detection limit was 0. 016 78 mg/L for manganese（ Ⅱ ） ion. And it was proved to be a low-cost, simple, rapid, sensitive, low-limit method. Functionalized nanoparticles are hopeful to use as fluorescence probe in detecting trace elements in biological samples.