Copper Ion Detection Method Based on a Quantum Dot CdTe Fluorescent Probe

Abstract

This study aimed to establish a high-sensitivity and high-selectivity method for the rapid detection of heavy metals, such as Cu2+, in water. The heavy metal ion Cu2+ was used as the research object, and the cadmium telluride quantum dot solution modified with cysteine and glutathione was used to detect Cu2+. The compound of Cu2+ on the surface and the modified quantum dots caused fluorescence quenching of the quantum dots. A linear relationship was observed between the concentration and the changing intensity of fluorescence quenching. This linear relationship was used to achieve the quantitative detection of Cu2+ content in the solution by quantum dots. In a certain experimental environment, the preprocessing of the standard normal variables of the characteristic band and the partial least squares modeling and analysis produced good self-prediction and actual prediction capabilities. The correction factor was 0.9006; the root mean square prediction error of correction was 8.83084 µmol/L; the coefficient of determination for the validation set was 0.8686; and the root mean square error of prediction was 5.4320 µmol/L.