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 Cr3+, Ag+ and Cu2+ ions. Cr3+ and chromium (III) picolinate could be quantitatively measured after masking Cu2+ and Ag+ ions by sulfide. Under optimal conditions, linear quenching was observed for Cr3+ in the ranges of 0-2.0 μM and the limit of detection was 3.0 nM. The recoveries for Cr3+ 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.