基于高场非对称波形离子迁移谱的生化传感器的设计

摘要

基于高场非对称波形离子迁移谱原理设计了一种由离子源,迁移区和检测器3部分组成的生化传感器.传感器采用真空紫外灯作离子源,高纯氮(99.999%)为载气,在常压下工作.加工了两种由两平行金属极板组成的迁移区,一种由两平板铜块组成,尺寸为25 mm×10 mm×1 mm;另外一种由微机电(MEMS )工艺加工,尺寸为20 mm×10 mm×1.5 mm.MEMS工艺加工的迁移区间距为1.5 mm,电场强度＜10 000 V/cm,不能过滤丙酮离子;铜块迁移区间距为1 mm,电场强度＞10 000 V/cm.当方波非对称射频电压峰峰值为1 600 V,频率为195.8 kHz,占空比为30%,补偿电压为-8.63 V时,采用平板铜块迁移区实现了丙酮离子的位移补偿,实验结果验证了传感器的性能.%A novel biochemcal sensor based on a high-Field Asymmetric Ion Mobility Spectrometry(FAIMS) theory is fabricated and characterized, which is mainly composed of an ionization source, a drift tube and a detector. By taking a VUV lamp as the ionization source and choosing an acetone with nitrogen (99.999%) as the carrier gas, the biochemical sensor works at ambient pressure.Moreover, two kinds of drift tubes consisting of two parallel plate electrodes are fabricated. One drift tube with the dimension of 25 mm×10 mm×1 mm is composed of two copper planar electrodes, the other with the dimension of 20 mm×10 mm×1.5 mm is fabricated by Micro Electro-Mechanical System(MEMS ) technology. For the former, the gap between the two drift tubes is 1 mm and the electrical field is above 10 000 V/cm; but for the latter, the gap between MEMS drift tube is 1.5 mm and the electrical field is less than 10 000 V/cm, which can not separate the acctone. With a peak-peak of rectangular asymmetric waveform voltage up to 1 600 V,a frequency of 195.8 kHz,a duty cycle of 30% and a compenstaion voltage of -8.63 V, the acetone displacement is compensated and the sensor ability to separate ions is demonstrated by an experiment using the planar copper drift tube.