单片集成微型气相色谱芯片研究

Study of Monolithic Integrated Micro Gas Chromatography Chip

基于微机电系统(Micro-electro-mechanical systems,MEMS)技术制备了一种由微色谱柱和微热导检测器构成的单片集成微型气相色谱(Micro gas chromatography,μGC)芯片。与现有集成芯片相比,在高深宽比的微沟道内构筑了一层高比表面积的介孔二氧化硅纳米颗粒薄膜作为固定相,有效提高了微色谱柱的柱容量和分离性能;微色谱柱的入口和出口处采用稳固的悬浮型微热敏结构,提高了器件的热隔离性能和稳定性。实验结果表明,此单片集成芯片可实现基线分离轻烃类混合气体组分(甲烷,乙烷,丙烷和丁烷),分析检测时间为33 s。其中,乙烷和丙烷的分离度为8.34,丙烷的理论塔板数高达11420。单片集成微型气相色谱芯片具有高分离度、高柱效、分析检测时间短等优点,特别适用于便携式气相色谱与野外实地检测。

A monolithic micro gas chromatography(μGC)chip integrated by a micro separation column(μSC)and a micro thermal conductivity detector(μTCD)was fabricated based on micro-electro-mechanical system(MEMS)technique.Compared with the state of the art,theμSC with high depth-to-width ratio channels,coated with mesoporous silica nanoparticles as stationary phase,could effectively improve the column capacity and separation performance.Besides,the stable suspendingμTCD,which was designed and fabricated in two ports of theμGC chip,could availably enhance the thermal isolation and reliability of the device.The mixture of light hydrocarbons(methane,ethane,propane and butane)could be separated by base line and detected by this monolithic integratedμGC chip,in which the overall analysis and detection time was only 33 seconds,the separation resolution of ethane and propane was 8.34,and the number of theoretical plates was as high as 11420.This monolithic integratedμGC chip had the advantages including good separation resolution,high column efficiency and short analysis time,which was highly suitable for portable gas chromatographic field and onsite detection.