CdTe量子点荧光法测定阳离子表面活性剂

Fluorescence detecting cationic surfactants using luminescent CdTe quantum dots as probes

合成了巯基乙酸(TGA)保护的水溶性发光CdTe量子点,并考察了此探针在阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB)中的发光行为。根据观察到的发光猝灭效应,建立了一种简单的测定阳离子表面活性剂的方法。考察了CdTe量子点的浓度、体系酸度、反应时间及共存物质等对测定的影响。在最佳条件下,CdTe量子点发光强度与CTMAB的浓度分别在6×10-7~9.0×10-6mol/L和1.2×10-5~3.8×10-5mol/L范围内分段成线性关系。该方法用于水样的阳离子表面活性剂的测定,回收率为97%~102%。

Water-soluble thioglycolic acid(TGA)-protected CdTe quantum dots were synthesized according to the literature,and the luminescence behavior of the probes in cationic surfactants CTAB was investigated.A facile method for the determination of cationic surfactants has been developed based on the quenching effect of CTAB on the luminescence of CdTe quantum dots.The effects of concentration of luminescent CdTe quantum dots,pH,reaction time,and coexisted materials on the determination have been investigated.Under the optimum conditions,the luminescence intensity was proportional to the CTAB concentration in the range of 6×10-7～9.0×10-6 mol/L and 1.2×10-5～3.8×10-5 mol/L,respectively.This method has been used to determine trace CS in water samples,and the recoveries are 97%～102%.