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Updated: Jul 7, 2026

Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
Cadmium telluride quantum dots as pH-sensitive probes for tiopronin determination
Yun-Qing Wang1, Chao Ye, Zheng-Hui Zhu
1Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, Nanjing 210009, China.
Abstract:
The pH-sensitive cadmium telluride (CdTe) quantum dots (QDs) were used as proton probes for tiopronin determination. Based on the fluorescence quenching of CdTe QDs caused by tiopronin, a simple, rapid and specific quantitative method was proposed. Under the optimal conditions, the calibration plot of ln(F(0)/F) with concentration of tiopronin was linear in the range of 0.15-20 microg mL(-1)(0.92-122.5 micromol L(-1)) with correlation coefficient of 0.998. The limit of detection (LOD) (3sigma/k) was 0.15 microg mL(-1)(0.92 micromol mL(-1)). The content of tiopronin in pharmaceutical tablet was determined by the proposed method and the result agreed with that obtained from the oxidation-reduction titration method and the claimed value.
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