标题：Facile fabrication of an aptasensor for thrombin based on graphitic carbon nitride/TiO2with high visible-light photoelectrochemical activity
作者：Fan, Dawei ;Guo, Cuijuan ;Ma, Hongmin ;Zhao, Di ;Li, Yina ;Wu, Dan ;Wei, Qin
作者机构：[Fan, Dawei ;Guo, Cuijuan ;Ma, Hongmin ;Zhao, Di ;Li, Yina ;Wu, Dan ;Wei, Qin ] Key Laboratory of Chemical Sensing & Analysis in Universities of Shand 更多
来源：Biosensors and Bioelectronics
摘要：A novel aptasensor for thrombin with high visible-light activity was facilely fabricated based on graphitic carbon nitride/TiO2(g-C3N4/TiO2) photoelectrochemical (PEC) composite. Crystallization of TiO2nanoparticles (NPs) and their strong interaction with g-C3N4sheet were confirmed by high-resolution transmission electron microscope (HR-TEM), both of which contributed to the high photocurrent intensity under visible-light irradiation. Carboxyl functionalized thrombin aptamers were first successfully bound to the g-C3N4/TiO2modified electrode as proven by photoelectrochemical test and electrochemical impedance spectroscopy (EIS) analysis. Ascorbic acid was utilized as the electron donor for scavenging photo-generated holes and inhibiting light driven electron–hole pair recombination. The specific recognition between thrombin aptamer and thrombin led to the linear decrease of photocurrent with the increase of logarithm of thrombin concentration in the range of 5.0×10−13 mol L−1to 5.0×10−9 mol L−1with a detection limit of 1.2×10−13 mol L−1. This proposed low-cost, convenient and sensitive aptasensor showed promising applications in biosensor and photoelectrochemical analysis.
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