Enhanced photoelectrochemical behavior of CdS/WS2 heterojunction for sensitive glutathione biosensing in human serum
Enhanced photoelectrochemical behavior of CdS/WS2 heterojunction for sensitive glutathione biosensing in human serum
复制标题
CdS/WS2 异质结增强光电化学行为，用于人血清中敏感的谷胱甘肽生物传感
DOI：
10.20964/2018.08.48
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发表时间：
2018
影响因子：
1.5
通讯作者：
Xue Huaiguo
中科院分区：
文献类型：
--
作者：
Zang Yang;Hu Xin;Zhou Hui;Xu Qin;Huan Pang;Xue Huaiguo
利用CdS/WS 2异质结效应，建立了一种灵敏测定谷胱甘肽（GSH）的增强型光电化学生物传感器。采用分步组装的方法成功构建了CdS/WS 2光阳极，并通过提高入射光-电流转换效率和电子寿命证实了异质结构的形成，使CdS/WS 2光阳极的光电流响应比CdS量子点修饰电极提高了约310%.在光照条件下，CdS量子点的光生电子趋向WS 2纳米片并被驱动到ITO电极，相应的光生空穴可以将GSH连续氧化为谷胱甘肽二硫化物，导致光电流发生显著变化，这是由于有效的载流子分离。在优化的条件下，该传感器具有良好的传感性能，偏压为0 V（vs. Ag/AgCl），线性范围为20 ~ 2.5mM，检测限为5.82 μM，选择性高，稳定性好，稳定性可接受。此外，该传感器还用于人体血清中GSH的检测。这些结果表明，该传感策略对光电化学器件的发展具有指导意义，在分子诊断和生物分析方面具有广阔的前景。
This work develops an enhanced photoelectrochemical biosensor for sensitive determination of glutathione (GSH) by means of the heterojunction effect of CdS/WS 2 . The CdS/WS 2 photoanode was successfully constructed through the method of stepwise assembly, and achieved around 310% increase of photocurrent response in respect to CdS quantum dots (QDs) modified electrode due to the formation of heterostructure, which was identified by the elevation of incident-photon-to-current conversion efficiency and electron lifetime. Under illumination, with the photogenerated electrons of CdS QDs tended to WS 2 nanosheets and sequentially driven to ITO electrode, the corresponding photogenerated holes could continuously oxidize GSH into glutathione disulfide, leading to a remarkable photocurrent change because of the efficient charge carrier separation. Under the optimized conditions, the biosensor demonstrated excellent sensing performances with the low applied bias potential of 0 V (versus Ag/AgCl), wide linear range from 20 μM to 2.5 mM, desirable detection limit of 5.82 μM, as well as high selectivity, good stability and acceptable stability. Moreover, this biosensor was also utilized to the monitoring of GSH in human serum. These results suggested this sensing strategy has a guiding significance for the development of photoelectrochemical devices, showing great prospect in molecular diagnostics and bioanalysis.