Electrochemiluminescence Resonance Energy Transfer System: Mechanism and Application in Ratiometric Aptasensor for Lead Ion

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• 作者：Yan-Mei Lei ; Wei-Xing Huang ; Min Zhao ; Ya-Qin Chai ; Ruo Yuan ; Ying Zhuo
• 刊名：Analytical Chemistry
• 出版年：2015
• 出版时间：August 4, 2015
• 年：2015
• 卷：87
• 期：15
• 页码：7787-7794
• 全文大小：446K
• ISSN：1520-6882

文摘

In this paper, a novel electrochemiluminescence resonance energy transfer (ECL-RET) system from O₂/S₂O₈^{2鈥?/sup> to a kind of amino-terminated perylene derivative (PTC-NH₂) was demonstrated for the first time, which was then applied to construct a ratiometric aptasensor for lead ion (Pb2+) detection. First, gold-nanoparticles-functionalized fullerene nanocomposites (AuNPs@nano-C₆₀) were coated on a glassy carbon electrode (GCE), and then thiol-modified assistant probes (APs) were attached on AuNPs@nano-C₆₀/GCE. Then the resultant electrode was hybridized with capture probes (the aptamer of the Pb2+, abbreviated as CPs) to generate DNA duplexes, which could induce PTC-NH₂ to be intercalated into the dsDNA grooves by the electrostatic adsorption. Herein, ECL dual peaks at 鈭?.7 V (vs Ag/AgCl) and 鈭?.0 V (vs Ag/AgCl) were obtained when the prepared aptasensor was detected in air-saturated S₂O₈2鈥?/sup> solution, which could be attributed to the emission of excited dimmers (蟺-excimers) (1(NH₂鈥揚TC)₂*) and 1(O₂)₂*, respectively. In the presence of Pb2+, the dsDNA was unwound, and Pb2+ G-quadruplex structure was generated because of the highly specific affinity between Pb2+ and CPs, which made the PTC-NH₂ release from the electrode surface. As a result, the ECL signal at 鈭?.7 V was decreased, and the ECL signal around 鈭?.0 V was increased. By measuring the ratio of ECL intensities at two excitation potentials, the developed aptasensor exhibited the linear response range from 1.0 脳 10鈥?2 M to 1.0 脳 10鈥? M with a detection limit of 3.5 脳 10鈥?3 M (S/N = 3) for Pb2+, which could offer an alternative analytical method with excellent properties of high selectivity, accuracy, and sensitivity.}