Carbon-Dot-Based Ratiometric Fluorescent Probe for Imaging and Biosensing of Superoxide Anion in Live Cells
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- 作者：Xiang Gao ; Changqin Ding ; Anwei Zhu ; Yang Tian
- 刊名：Analytical Chemistry
- 出版年：2014
- 出版时间：July 15, 2014
- 年：2014
- 卷：86
- 期：14
- 页码：7071-7078
- 全文大小：437K
- ISSN：1520-6882
文摘
In this article, a ratiometric fluorescent biosensor for O2鈥⑩€?/sup> was developed, by employing carbon dots (C-Dots) as the reference fluorophore and hydroethidine (HE), a specific organic molecule toward O2鈥⑩€?/sup>, playing the role as both specific recognition element and response signal. The hybrid fluorescent probe CD-HE only emitted at 525 nm is ascribed to C-Dots, while HE was almost nonfluorescent, upon excitation at 488 nm. However, after reaction with O2鈥⑩€?/sup>, a new emission peak ascribed to the reaction products of HE and O2鈥⑩€?/sup> was clearly observed at 610 nm. Meanwhile, this peak gradually increased with the increasing concentration of O2鈥⑩€?/sup> but the emission peak at 525 nm stayed constant, leading to a ratiometric detection of O2鈥⑩€?/sup>. The inorganic鈥搊rganic fluorescent sensor exhibited high sensitivity, a broad dynamic linear range of 5 脳 10鈥?鈥?.4 脳 10鈥? M, and low detection limit down to 100 nM. The present probe also showed high accuracy and excellent selectivity for O2鈥⑩€?/sup> over other reactive oxygen species (ROS), metal ions, and so on. Moreover, the C-Dot-based inorganic鈥搊rganic probe demonstrated long-term stability against pH changes and continuous light illumination, good cell-permeability, and low cytotoxicity. Accordingly, the developed fluorescent biosensor was eventually applied for intracellular bioimaging and biosensing of O2鈥⑩€?/sup> changes upon oxidative stress.