Organic transistors are promising platforms for wearable biosensors. However, the strategies to improve signal amplification have yet to be determined, particularly regarding biosensors that generate very weak signals. In this study, an organic voltage amplifier is presented for a lactate sensor on flexible plastic foil. The preamplifier is based on a 3D complementary inverter, which is achieved by vertically stacking complementary transistors with a shared gate between them. The shared gate is extended and functionalized with a lactate oxidase enzyme to detect lactate. The sensing device successfully detects the lactate concentration in the human sweat range (20–60 mm) with high sensitivity (6.82 mV mm⁻¹) due to high gain of its amplification. The 3D integration process is cost‐effective as it is solution‐processable and doubles the number of transistors per unit area. The device presented in this study would pave the way for the development of high‐gain noninvasive sweat lactate sensors that can be wearable.

中文翻译：

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用于乳酸传感器的灵活 3D 有机前置放大器。

有机晶体管是可穿戴生物传感器的有前途的平台。然而，改善信号放大的策略尚未确定，特别是关于产生非常微弱信号的生物传感器。在这项研究中，提出了用于柔性塑料箔上的乳酸传感器的有机电压放大器。前置放大器基于 3D 互补反相器，这是通过垂直堆叠互补晶体管实现的，它们之间具有共享栅极。使用乳酸氧化酶对共享门进行扩展和功能化以检测乳酸。感测装置成功地检测在人类汗液范围的乳酸浓度（20-60米米以高灵敏度）（6.82毫伏米米^-1) 由于其放大的高增益。3D 集成工艺具有成本效益，因为它是可解决方案处理的，并且每单位面积的晶体管数量增加了一倍。本研究中展示的设备将为开发可穿戴的高增益无创汗液乳酸传感器铺平道路。