Fluorescence sensor based on glutathione capped CdTe QDs for detection of Cr3+ ions in vitamins

In this work, glutathione capped CdTe QDs (GSH-QDs) were prepared through a one-pot process and found to be quenched by Cr 3+ , Ag + and Cu 2+ ions. Cr 3+ and chromium (III) picolinate could be quantitatively measured after masking Cu 2+ and Ag + ions by sulfide. Under optimal conditions, linear quenching was observed for Cr 3+ in the ranges of 0–2.0   μM and the limit of detection was 3.0   nM. The recoveries for Cr 3+ in vitamin supplements obtained were from 92.5% to 106%. The determination results of chromium (III) picolinate in vitamin supplement samples were compared to that obtained using flame atomic absorption spectrometry (FAAS) method, and the result showed good reliability.