Herein, an innovative photocathodic enzymatic biosensor is proposed with poly {4,8-bis[5-(2-ethylhexyl)thiophen-2-yl]-benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophene-4,6-diyl} (PTB7-Th) as donor-acceptor-type photoactive material and three-dimensional (3D) polyaniline hydrogels (PAniHs) as both electron transfer layer and biomolecule carrier. Based on the enhancement effect of PAniHs on the charge separation and electron transfer of PTB7-Th and the competitive consumption of dissolved oxygen (O2) between the xanthine oxidase (XOD)-guanine catalytic reaction and O2-sensitive PTB7-Th/PAniHs, the proposed photocathodic enzymatic biosensor has been demonstrated to detect guanine with the advantages of low limit of detection (0.02 μM), wide linear range (from 0.1 to 80 μM), simple and convenient preparation process, satisfactory stability, and photochemical signal amplification independent of any exogenous electron donor/acceptor or sensitizer. Remarkably, the proposed photocathodic enzymatic biosensor can not only be extended to other aerobic enzymatic bioanalyses, but also pave a horizon for the application of environmentally friendly conductive hydrogel materials in photoelectrochemical bioanalysis.

中文翻译：

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三维供体-受体型光敏材料/导电聚苯胺水凝胶复合物，用于灵敏的光阴极酶生物分析。

在这里，提出了一种创新的光阴极酶生物传感器与聚{4,8-双[5-（2-（乙基乙基己基）噻吩-2-基]-苯并[1,2-b：4,5-b']二噻吩-2供体-受体型光敏材料,, 6-二基-alt-3-氟-2-[（（2-乙基己基）羰基]噻吩并[3,4-b]噻吩-4,6-二基}（PTB7-Th）和三维（3D）聚苯胺水凝胶（PAniHs）作为电子传输层和生物分子载体。基于PAniHs对PTB7-Th的电荷分离和电子转移以及黄嘌呤氧化酶（XOD）-鸟嘌呤催化反应和O2敏感的PTB7-Th / PAniHs之间的竞争性氧竞争消耗的增强作用，已证明拟议的光阴极酶生物传感器可检测鸟嘌呤，具有检测限低（0.02μM），线性范围宽（0.1至80μM），制备过程简单方便，稳定性令人满意，光化学信号放大不受任何外源电子供体/受体或敏化剂的影响。值得注意的是，所提出的光阴极酶生物传感器不仅可以扩展到其他有氧酶生物分析，而且为在光电化学生物分析中应用环境友好的导电水凝胶材料奠定了基础。