Sadeghi Susan, Hosseinpour-Zaryabi Mohadeseh
Department of Chemistry, Faculty of Science, University of Birjand, Birjand, Iran.
Luminescence. 2020 Dec;35(8):1391-1401. doi: 10.1002/bio.3903. Epub 2020 Aug 5.
A simple turn on/off fluorescence approach based on dithizone-capped ZnS quantum dots (ZnS@DZ QDs) with the help of lead ions as a fluorescent probe for the quantitative determination of quercetin is reported. The interaction of lead ions with dithizone led to the formation of a rigid structure on the surface of ZnS@DZ QDs and turned on the fluorescence intensity of the QDs. After addition of quercetin to this probe and interaction with lead ions, the fluorescence emission turned off. Concerning the quenching fluorescence intensity of ZnS@DZ QDs/Pb QDs probe induced by the target, under the optimum conditions, the probe enabled detection of quercetin in the concentration range from 0.54 μM to 21.7 μM with a correlation coefficient of 0.993 and detection limit of 0.25 μM. The present probe was applied successfully to the determine quercetin as a nutritional biomarker in human serum and 24-h urine samples.
报道了一种基于双硫腙包覆的硫化锌量子点（ZnS@DZ QDs），借助铅离子作为荧光探针用于槲皮素定量测定的简单开/关荧光方法。铅离子与双硫腙的相互作用导致在ZnS@DZ QDs表面形成刚性结构并开启量子点的荧光强度。向该探针中加入槲皮素并与铅离子相互作用后，荧光发射关闭。关于目标物诱导的ZnS@DZ QDs/Pb QDs探针荧光强度猝灭，在最佳条件下，该探针能够检测浓度范围为0.54 μM至21.7 μM的槲皮素，相关系数为0.993，检测限为0.25 μM。本探针已成功应用于测定人体血清和24小时尿液样本中作为营养生物标志物的槲皮素。
