将三重信号放大策略与内置双电极和外部储能装置集成，制造出一种新型自供电生物传感器，用于超灵敏检测 miRNA-21。具体来说，通过催化发夹组装（CHA）在生物阴极和生物阳极表面修饰DNA四面体和haripin2-葡萄糖氧化酶，实现双重信号放大。此外，通过外部电容器实现三重信号放大。因此，所构建的自供电生物传感器在 0.1 fM 至 10 pM 范围内对 miRNA-21 检测显示出 0.06 fM 的低检测限。这项研究提出了一种及时检测癌症的实用且灵敏的方法。

A triple signal amplification strategy was integrated with a built-in double electrode and external energy storage device to fabricate a novel self-powered biosensor for ultrasensitive detection of miRNA-21. Specifically, DNA tetrahedra and haripin2-glucose oxidase are modified on the surface of the biocathode and bioanode by catalytic hairpin assembly (CHA) to achieve dual signal amplification. Moreover, triple signal amplification is realized by including an external capacitor. Consequently, the as-constructed self-powered biosensor demonstrates a low detection limit of 0.06 fM toward the miRNA-21 assay within the range of 0.1 fM to 10 pM. This study presents a practical and sensitive approach to timely cancer detection.