Photoelectrochemical (PEC) biosensing, recognized for its heightened sensitivity, faces limitations in its application for in vivo diagnosis due to the inefficiency of UV–visible light-driven photoactive materials in nontransparent biological samples. In this study, we investigate the potential of an S-scheme all-polymer heterojunction comprising a prototype nonfullerene polymeric acceptor (PYIT) and carbon nitride to develop a near-infrared (NIR) light-driven PEC biosensor for monitoring acetylcholinesterase activity in nontransparent human whole blood. The distinct molecular structure of PYIT enables efficient light absorption in the NIR region, enhancing sensitivity in nontransparent biological samples. The biosensor functions via a proton-dependent conversion mechanism between PYIT-OH and PYIT, leveraging the selective and reversible chemical reactivity of the moieties in backbone, eliminating the need for traditional and intricate integration of a biorecognition unit. Our findings demonstrate a direct correlation between variations in photoelectric performance and acetylcholinesterase concentration, showcasing exceptional sensitivity, selectivity, and reversibility.

中文翻译：

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通过 S-Scheme 全聚合物共混物进行近红外光驱动的可逆光电化学生物测定，用于乙酰胆碱酯酶活性监测


光电化学 （PEC） 生物传感以其更高的灵敏度而著称，但由于紫外-可见光驱动的光活性材料在不透明生物样品中的效率低下，因此在体内诊断中的应用面临限制。在这项研究中，我们研究了由原型非富勒烯聚合物受体 （PYIT） 和氮化碳组成的 S 型全聚合物异质结的潜力，以开发一种近红外 （NIR） 光驱动的 PEC 生物传感器，用于监测不透明人全血中的乙酰胆碱酯酶活性。PYIT 独特的分子结构能够在 NIR 区域有效吸收光，从而提高不透明生物样品的灵敏度。生物传感器通过 PYIT-OH 和 PYIT 之间的质子依赖性转换机制发挥作用，利用骨架中部分的选择性和可逆化学反应性，无需传统和复杂的生物识别单元集成。我们的研究结果表明，光电性能的变化与乙酰胆碱酯酶浓度之间存在直接关联，显示出卓越的灵敏度、选择性和可逆性。