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

针对微创医疗的需要，提出了利用MEMS技术研制仿蚊子喙的微针。用放大透镜和高速摄影系统观察了蚊喙对实验室透明薄皮肤的穿透运动。通过观察证实了以下事实：（a）两个上颌骨插入人体皮肤生物体中，起着锚的作用。(b)唇插入两个上颌骨之间的空间。循环地重复（a）和（B）的过程，同时长鼻在对象内部更深地前进。还对各种参数进行了定量评价，如插入速度，周期时间等。考虑到蚊子的长鼻的插入机制，使用动态有限元模拟和实验上开发的设备（组合微针），它被证明，组合针的合作交替运动是非常有效的，减少穿透皮肤所需的力。此外，实现了具有尖锐尖端的微针，其阻力远小于商业柳叶刀针的阻力。

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.