Fluorescence enhancement of CdTe/CdS quantum dots by coupling of glyphosate and its application for sensitive detection of copper ion

A novel fluorescent probe for Cu2+ determination based on the fluorescence quenching of glyphosate (Glyp)-functionalized quantum dots (QDs) was firstly reported. Glyp had been used to modify the surface of QDs to form Glyp-functionalized QDs following the capping of thioglycolic acid on the core-shell CdTe/CdS QDs. Under the optimal conditions, the response was linearly proportional to the concentration of Cu2+ between 2.4 x 10(-2) mu g mL(-1) and 28 mu g mL(-1), with a detection limit of 1.3 x 10(-3) mu g mL(-1) (3 delta). The Glyp-functionalized QDs fluorescent probe offers good sensitivity and selectivity for detecting Cu2+. The fluorescent probe was successfully used for the determination of Cu2+ in environmental samples. The mechanism of reaction was also discussed. (c) 2012 Elsevier B.V. All rights reserved.