Zhuo Shujuan, Gong Jiajia, Zhang Ping, Zhu Changqing
Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Chemo-Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, PR China.
Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Chemo-Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, PR China.
Talanta. 2015 Aug 15;141:21-5. doi: 10.1016/j.talanta.2015.03.054. Epub 2015 Apr 1.
In this paper, we have presented a novel CdTe quantum dots (QDs) based fluorescent sensor for visual and turn-on sensing of citrate in human urine samples. The europium ion (Eu(3+)) can lead to the fluorescence quenching of thioglycollic acid (TGA) modified CdTe QDs due to photoinduced electron transfer accompanied by the change of emission color from yellow to orange. Next, addition of citrate breaks the preformed assembly because citrate can replace the CdTe QDs, based on the fact that the Eu(3+) ion displays higher affinity with citrate than the CdTe QDs. Thus the photoinduced electron transfer is switched off, and the fluorescence emission of CdTe QDs is rapidly (within 5min) recovered, simultaneously, the orange emission color restores to yellow. Such proposed strategy may conveniently discriminate the patient of renal stone from normal person by naked eyes. In addition to visualization detection, the fluorescence responses can be used for well quantifying citrate in the range of 0.67-133μM. So, the present, simple, low-cost and visualized citrate fluorescence sensor has great potential in the applications for earlier screening in clinical detection.
在本文中，我们展示了一种基于新型碲化镉量子点（QDs）的荧光传感器，用于对人体尿液样本中的柠檬酸盐进行可视化和开启式传感。铕离子（Eu(3+)）会导致巯基乙酸（TGA）修饰的碲化镉量子点发生荧光猝灭，这是由于光诱导电子转移，同时发射颜色从黄色变为橙色。接下来，加入柠檬酸盐会破坏预先形成的组装体，因为基于Eu(3+)离子与柠檬酸盐的亲和力高于碲化镉量子点这一事实，柠檬酸盐可以取代碲化镉量子点。因此，光诱导电子转移被关闭，碲化镉量子点的荧光发射迅速（在5分钟内）恢复，同时，橙色发射颜色恢复为黄色。这种提出的策略可以通过肉眼方便地将肾结石患者与正常人区分开来。除了可视化检测外，荧光响应还可用于在0.67 - 133μM范围内对柠檬酸盐进行良好的定量。所以，这种目前简单、低成本且可视化的柠檬酸盐荧光传感器在临床检测早期筛查应用中具有巨大潜力。
