In response to the health risks posed by heavy metal lead, we have developed a self-powered sensor specifically designed for detection of lead ions in this work. This sensor is designed based on an enzyme-free biofuel cell as a self-powered source. The biofuel cell utilizes two-dimensional lamellar Au NPs-TiCTx heterostructures as the capacitive anode substrate material. The TiCTx MXene with the excellent charge storage capacity and fast discharge characteristics, provides a large instantaneous current for signal amplification. Furthermore, the DNA walker technique was combined to regulate the loading of ultra-small Au NPs exhibiting glucose oxidase-like properties. Meanwhile, Co, Mn nitrogen-doped carbon-based nanosheets were designed as the cathode with outstanding oxygen reduction reaction catalytic activity. As a result, the constructed enzyme-free biofuel cell has been used to detect Pb with a wide linear range (0.01–7500 nM) and a low detection limit (0.43 pM). It has been successfully applied to the determination of Pb in human plasma, achieving excellent recovery rates (94.0–110.5 %). The developed capacitive anodes not only significantly optimized the performance of the biofuel cell self-powered sensors, but also provided important insights for the future design and construction of biofuel cells.

中文翻译：

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基于 Mxene 的电容式无酶生物燃料电池自供电传感器，用于检测人体血浆中的铅离子


针对重金属铅带来的健康风险，我们在这项工作中开发了一种专门用于检测铅离子的自供电传感器。该传感器是基于无酶生物燃料电池作为自供电源而设计的。该生物燃料电池采用二维层状Au NPs-TiCTx异质结构作为电容阳极基底材料。 TiCTx MXene具有优异的电荷存储能力和快速放电特性，为信号放大提供瞬间大电流。此外，结合 DNA walker 技术来调节具有葡萄糖氧化酶样特性的超小 Au NP 的负载。同时，设计了Co、Mn氮掺杂碳基纳米片作为阴极，具有优异的氧还原反应催化活性。因此，构建的无酶生物燃料电池已用于检测 Pb，具有宽线性范围 (0.01–7500 nM) 和低检测限 (0.43 pM)。它已成功应用于人体血浆中 Pb 的测定，取得了优异的回收率 (94.0–110.5%)。所开发的电容阳极不仅显着优化了生物燃料电池自供电传感器的性能，而且为生物燃料电池的未来设计和构建提供了重要的见解。