Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin; consequently, blood glucose levels increase to become abnormally high. Accordingly, the primary treatment of diabetes is to control glycemic levels continuously. To continuously control glycemic levels, several medical devices have been developed to monitor blood glucose levels, represented by sensors and monitors for the self-monitoring of blood glucose. The ultimate goal for those engaged in research to develop medical devices is to develop implantable biodevices, namely self-powered autonomously operated artificial pancreas systems. One of the most challenging issues in realizing an implantable artificial pancreas is the long-term continuous supply of electricity, which is currently dependent on rechargeable batteries, requiring periodical replacement. In this work, we report the development of a direct electron transfer type enzyme-based miniaturized self-powered glucose sensor based on the BioCapacitor principle with a micro-sized enzyme anode area (0.15 mm 0.75 mm), which has only 0.1 mm² of electrode surface. As a result, a BioCapacitor utilizing a biofuel cell with a micro-sized enzyme anode was operated by self-power. In addition, the glucose concentration was detected within the range from 13 mM to 100 mM based on the frequency of charge/discharge cycles of the BioCapacitor. Although further improvement of the current density of the micro-sized anode is necessary to monitor a glucose concentration range lower than 13 mM, this self-powered glucose sensor with a micro-sized electrode based on the BioCapacitor principle was operated continuously for 6.6 h at 37 C in 100 mM potassium phosphate buffer (pH 7.0). Our success indicates the potential to realize self-powered, autonomous, and implantable sensing modules for bio devices such as glucose-sensing systems for an artificial pancreas.

糖尿病是一种身体无法产生足够胰岛素或对胰岛素作出正常反应的疾病；因此，血糖水平升高到异常高。因此，糖尿病的主要治疗是持续控制血糖水平。为了持续控制血糖水平，已经开发了多种医疗设备来监测血糖水平，以自我监测血糖的传感器和监视器为代表。从事医疗器械研发的人员的最终目标是开发可植入的生物器械，即自供电自主操作的人工胰腺系统。实现植入式人工胰腺最具挑战性的问题之一是长期持续供电，目前依赖于可充电电池，需要定期更换。在这项工作中，我们报告了基于 BioCapacitor 原理的直接电子转移型酶基小型自供电葡萄糖传感器的开发，该传感器具有微型酶阳极面积（0.15 mm × 0.75 mm），只有 0.1 mm²电极表面。结果，利用带有微型酶阳极的生物燃料电池的生物电容器通过自供电运行。此外，根据生物电容器的充电/放电循环频率，在 13 mM 至 100 mM 的范围内检测到葡萄糖浓度。尽管需要进一步提高微型阳极的电流密度以监测低于 13 mM 的葡萄糖浓度范围，但这种基于 BioCapacitor 原理的带有微型电极的自供电葡萄糖传感器在在 37°C 的 100 mM 磷酸钾缓冲液 (pH 7.0) 中。我们的成功表明，有可能为生物设备（如人工胰腺的葡萄糖传感系统）实现自供电、自主和可植入的传感模块。