以CdSe/CdS量子点(CdSe/CdS QDs)为原料,对其进行硅烷氨基化表面修饰,合成了具有水溶性的发光量子点(CdSe/CdS-Si-NH2 QDs)探针。基于量子点与持久性有机污染物(POPs)发生共振能量转移及偶联反应等过程而导致荧光变化的现象,分别利用荧光光谱、三维荧光光谱和荧光猝灭原理测定芘、荧蒽和酞酸酯浓度。结果表明,构建的测定方法对芘、荧蒽和酞酸酯的检测限均达到pg/L水平,将CdSe/CdS-Si-NH2QDs应用于三峡库区(万州段)水体芘、荧蒽和酞酸酯含量的测定,3种污染物的加标回收率为89.5%-106.4%,达到了定量灵敏测定的要求,根据分析结果,对三峡库区污染物的来源进行了分析。
The water soluble light-emitting quantum dots (CdSe/CdS-Si-NH2 QDs) probe was synthesized by surface modification of CdSe/CdS QDs using silane amination. The resonance energy transfer and coupling reaction between persistent organic pollutants (POPs) and quantum dots would cause fluorescence changes. With the help of fluorescence spectrum, three-dimensional fluorescence spectrum, and fluorescence quenching techno logy, a novel method was proposed to detect 3 typical POPs (pyrene,fluoranthene and phthalate ester). Results showed that the established method was sensitive with the detection limit of pg/L level for 3 pollutants. The synthesized CdSe/CdS-Si-NH2 QDs was used to analyze pyrene, fluoranthene and phthalate ester in water of Wanzhou Part of the Three Gorges Reservoir region. The recovery values were satisfactory (89.5 %-106.4% ), demonstrating that this fluorescence method was suitable for detecting the real water samples. Finally,the sources of the pollutants in Three Gorges Reservoir region was analyzed.