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Fluorescence quenching determination of metallothioneins using 8-hydroxyquinoline-5-sulphonic acid-Cd(II) chelate
Qiu-Mei Qian1, Yong-Sheng Wang, Bin Zhou
1College of Public Health, University of South China, Hengyang 421001, PR China.
Abstract:
A novel method for the determination of metallothioneins (MTs) in urine was developed by fluorescence quenching strategy. The response signals linearly correlated with the concentration of MTs in the ranges of 3.12×10(-8)-1.23×10(-6) mol L(-1), and the limit of detection (LOD) was 9.36×10(-9) mol L(-1). The proposed method avoids the label and derivatization steps in common methods, and is reliable, inexpensive and sensitive. Furthermore, the interaction of MTs and 8-hydroxyquinoline-5-sulphonic acid (HQS)-Cd(II) chelate was investigated, and a static quenching mode was proposed to be primarily responsible for the fluorescence quenching event. It could provide a promising potential for the detection of the biomacromolecules which have no native fluorescence, and be benefit to extend the application of fluorescence strategy.
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