面向航天医学应用的体液预处理仪研制

本文基于微流控技术研制了面向航天医学应用的体液预处理芯片及仪器,以便对航天员体液进行医学检测。体液预处理芯片集成了驱动液体和控制流路的微泵微阀,通过控制微泵微阀可实现从进样、不同功能的预处理到输出样品整个过程的自动操作。此外在常规样品预处理功能的基础上,还集成了排气泡功能,使预处理芯片能够在太空微重力环境下对有气泡的体液进行体液预处理。预处理仪集微泵微阀驱动机构和芯片液面位置检测机构于一体,能够实现多种体液预处理模式,且与芯片间无需任何管路及电连接,方便芯片更换。利用有限元仿真软件对预处理仪进行了航天环境下的各项力学分析,包括模态分析、加速度过载分析、正弦扫描分析及随机振动分析,得到了预处理仪机械结构在不同载荷条件下的应力分布,结果显示最大应力值为57.37 MPa,经过校核得知满足航天环境强度要求。最后,基于制作的排气混合预处理芯片进行了预处理实验,结果表明芯片的排气和混合效果良好。

Development of a body fluids pretreatment instrument for aerospace medicine

Pretreatment microfluidic chip and instrument for aerospace medicine were designed and developed based on microfluidics technology to realize astronauts'' body fluids (saliva, urine, blood, etc) medical assay in microgravity environment.The chips integrated with micropumps and microvalves, can automatically implement total pretreatment processes including sample introduction, different kinds of pretreatments and sample delivering out through the instrument operation.At the same time, the chips integrated a degassing function, assuring that it can be suitable to deal with the body fluids with bubbles and be used in microgravity environment.The pretreatment instrument consists of driving mechanisms of micropumps and microvalves and a detection module of liquid level, so it can be utilizable for different pretreatments without any pipe and electric connection, letting replace chips easily.All mechanical analyses in aerospace environment for instrument were conducted by finite elements simulation software, including modal analysis, overload analysis of accelerated speed, sinusoid scan analysis and random vibration analysis to obtain stress distribution of mechanical structure of pretreatment instrument in different load conditions.The results indicate that maximal stress value was 57.37 MPa, satisfying the strength requirement of space environment.Finally, pretreatment experiment was conducted based on mixed pretreatment chip of degassing mode to indicate good effect of degassing and mix of chip in the result.