Determination of Trace Cadmium in Water Samples Based on CdTe Quantum Dot Fluorescent Probes

In this paper,CdTe quantum dots were systhesized in aqueous solution with thioglycolic acid(TGA)as the stabilizing agent.A novel method has been developed for Cd2+ determination based on the fluorescence enhancement of CdTe QDs by Cd2+.The results showed that,the fluorescence intensity of CdTe QDs could significantly be enhanced by Cd2+.There was a good linear relationship between the fluorescence intensity of CdTe QDs and Cd2+ concentration.Under optimum conditions,the linear range was 2.0×10-7-5.5×10-5g/L with a detection limit of 3.2×10-8 g/L(3s/k).This method has good stability,wide linear range and low detection limit as well as good anti-interference ability.It was applied to the analysis of water samples with the recoveries of 96.0%-102.5%.