A sensitive assay of chelerythrine using a fluorescence quenching approach with glutathione capped CdTe/CdS quantum dots as a probe

A sensitive and simple method for the determination of chelerythrine (CHE) was developed based on the fluorescence quenching effect of CHE for glutathione (GSH)-capped CdTe/CdS quantum dots (QDs). Under optimum conditions, a good linear relationship was obtained from 0.073 to 24.0 μg mL−1 with a correlation coefficient of 0.9988, and the detection limit (3σ/κ) was 21.9 ng mL−1. The fluorescence quenching mechanism that has been proposed is based on electron transfer supported by ultraviolet-visible (UV-vis) absorption, fluorescence (FL) spectroscopy and electrochemical techniques. The method has been applied to the determination of CHE in synthetic samples and fresh serum samples from healthy humans with satisfactory results. The proposed method manifested several advantages such as high sensitivity, short analysis time, low cost and ease of operation.