Observation of Mosquito's Penetrating Motion and Its Application to Microneedle for Low-invasive Medical Treatment

以低侵入性医疗为目标，提出了利用MEMS技术研制模拟蚊子喙的微针。用放大镜和高速摄像系统观察了蚊子的喙部穿透透明薄皮的运动。观察证实了以下事实：(a)两条上颌骨插入人体皮肤组织，起锚定作用。(b)阴唇插入两上颌骨之间的空隙。(a)和(b)的过程循环重复，而吻在物体内部深入。并对插入速度、循环时间等参数进行了定量评价。针对蚊子喙部的插入机理，采用动态有限元模拟和实验相结合的方法，对研制的组合式微针进行了仿真研究，证明了组合式微针的协同交替运动可以有效地减小刺入皮肤所需的力。并且实现了针尖锋利的微针，其阻力比商用柳叶刀针小得多。

Aiming at use for low-invasive medical treatment, development of microneedle imitating mosquito's proboscis using MEMS technology was proposed. A penetrating motion of mosquito's proboscis to a transparent thin skin of laboratory lat was observed by a magnifying lens and high-speed camera system. Following facts were confirmed by the observation : (a) two maxillas are inserted to human skin organism, playing a role of anchor. (b) Labium is inserted to the space between two maxillas. The procedures of (a) and (b) are cyclically repeated, while the proboscis progresses deeper inside the object. Also various parameters were quantitatively evaluated such as insertion speed, cycle time, etc. Considering insertion mechanism of mosquito's proboscis using both dynamic FEM simulation and experiment on a developed device (combined microneedle), it was proven that the cooperative alternative motion of combined needles is much effective for reducing the necessary force for penetrating the skin. Moreover, a microneedle with sharp tip was realized, resistance force of which was much smaller than that of a commercial lancet needle.