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 Cu 2+ 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 Cu 2+ between 2.4   ×   10 −2   μg   mL −1 and 28   μg   mL −1 , with a detection limit of 1.3   ×   10 −3   μg   mL −1 (3 δ ). The Glyp-functionalized QDs fluorescent probe offers good sensitivity and selectivity for detecting Cu 2+ . The fluorescent probe was successfully used for the determination of Cu 2+ in environmental samples. The mechanism of reaction was also discussed.