For future medical microrobotics, we have proposed the concept of the electroosmotic self-propulsive microswimmer powered by biofuel cell. According to the derived theoretical model, its self-propulsion velocity is inversely proportional to the length of the microswimmer, while it is proportional to the open circuit potential generated by the biofuel cell which does not depend on its size. Therefore, under conditions where those mechanisms work, it can be expected that the smaller its microswimmer size, the faster its self-propulsion velocity. Because of its remarkable feature, this concept is considered to be suitable as propulsion mechanisms for future medical microrobots to move inside the human body through the vascular system, including capillaries. We have already proved the mechanisms by observing the several 10 μm/s velocity of 100 μm prototypes fabricated by the optical photolithography using several photomasks and alignment steps. However, the standard photolithography was not suitable for further miniaturization of prototypes due to its insufficient resolution. In this research, we adopted femtosecond-laser 3D microlithography for multi-materials composing of the conductive polymer composites and nonconductive polymer composite and succeeded in fabricating 10 μm prototypes. Then we demonstrated more than 100 μm/s velocity of the prototype experimentally and proved its validity of the smaller and faster feature.

中文翻译：

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生物燃料电池驱动的电渗自推进微游泳器的小型化效果

对于未来的医学微型机器人，我们提出了由生物燃料电池驱动的电渗自推进微游泳器的概念。根据导出的理论模型，其自推进速度与微掠器的长度成反比，而与生物燃料电池产生的开路电势成正比，而电势不取决于其大小。因此，在那些机制起作用的条件下，可以预期的是，它的微型扫描器尺寸越小，其自推进速度就越快。由于其卓越的功能，该概念被认为是适合将来的微型医疗机器人通过血管系统（包括毛细血管）在人体内部移动的推进机制。我们已经通过观察光学光刻使用几个光掩模和对准步骤制造的100μm原型的几个10μm/ s速度来证明了这种机理。但是，标准光刻技术由于分辨率不足而不适用于原型的进一步小型化。在这项研究中，我们将飞秒激光3D微光刻技术用于由导电聚合物复合材料和非导电聚合物复合材料组成的多种材料，并成功制造了10μm的原型。然后，我们通过实验证明了原型的速度超过100μm/ s，并证明了其较小和较快功能的有效性。由于其分辨率不足，标准光刻技术不适合进一步小型化原型。在这项研究中，我们将飞秒激光3D微光刻技术用于由导电聚合物复合材料和非导电聚合物复合材料组成的多种材料，并成功制造了10μm的原型。然后，我们通过实验证明了原型的速度超过100μm/ s，并证明了其较小和较快功能的有效性。由于其分辨率不足，标准光刻技术不适合进一步小型化原型。在这项研究中，我们将飞秒激光3D微光刻技术用于由导电聚合物复合材料和非导电聚合物复合材料组成的多种材料，并成功制造了10μm的原型。然后，我们通过实验证明了原型的速度超过100μm/ s，并证明了其较小和较快功能的有效性。