Comprehensive theoretical analysis and experimental exploration of ultrafast microchip‐based high‐field asymmetric ion mobility spectrometry (FAIMS) technique

Abstract

High-field asymmetric ion mobility spectrometry (FAIMS) has become an efficient technique for separation and characterization of gas-phase ions at ambient pressure, which utilizes the mobility differences of ions at high and low fields. Micro FAIMS devices made by micro-electromechanical system technology have small gaps of the channels, high electric field and good installation precision, as thus they have received great attentions. However, the disadvantage of relatively low resolution limits their applications in some areas. In this study, theoretical analysis and experimental exploration were carried out to overcome the disadvantage. Multiple scans, characteristic decline curves of ion transmission and pattern recognitions were proposed to improve the performance of the microchip-based FAIMS. The results showed that although micro FAIMS instruments as a standalone chemical analyzer suffer from low resolution, by using one or more of the methods proposed, they can identify chemicals precisely and provide quantitative analysis with low detection limit in some applications. Copyright © 2015 John Wiley & Sons, Ltd.

Portable FAIMS: Applications and future perspectives

“…There are IMS and FAIMS devices used to sniff out bombs by armed forces abroad and detect chemical warfare agents, 12, 13, 15, 17 as well as those used by the U.S. Transportation Security Administration to analyze the hands, shoes, and accessories of passengers wishing to depart from many airports around the country for explosives residue. 16 Previous work performed in the Yost Laboratory in recent years, both published 38 and unpublished, corroborates these findings.…”

“…IMS and FAIMS compliment MMS very well, and have proven capable of also providing in situ analysis in a variety of environments. Whether analyzing compounds in the upper atmosphere, 10, 11 detecting illegal substances in a person’s breath, 12–15 or being utilized for detection of chemical warfare agents, 12, 13, 16, 17 IMS and FAIMS have proven useful for analyzing samples similar to those seen with MMS. Portable IMS has been well defined in previous studies, 12, 17 hence, this work will focus on portable FAIMS.…”

High pressure effects in high-field asymmetric waveform ion mobility spectrometry

“…It was etched from a high‐conductivity silicon wafer, wire bonded on gold electrodes which were deposited by thermal evaporation, packaged and mounted onto a printed circuit board . The detailed fabrication and device structure can be found in our previous publications . The dispersion field ( E D ) applied across the gap has a range of 0–75 kV/cm, a frequency of 25 MHz, and a duty cycle of 0.33–0.35.…”

“…[17] The detailed fabrication and device structure can be found in our previous publications. [18,19] The dispersion field (E D ) applied across the gap has a range of 0-75 kV/cm, a frequency of 25 0.33-0.35. A compensation voltage in a range of ±3 V was applied to the electrodes, generating a field range of ±0.86 kV/cm which guarantees ions passing the channel to the detector at the exit.…”

Drone-Mountable Gas Sensing Platform Using Graphene Chemiresistors for Remote In-Field Monitoring

“…One strategy consists of miniaturizing the design of gas sensing technologies first developed in research in laboratories. This approach was used for gas chromatography/liquid chromatography-mass spectroscopy (GC/LC-MS) [ 4 , 5 ], and ion mobility spectroscopy (IMS) [ 6 , 7 , 8 ]. In these contexts, such an approach can ensure high sensitivity as well as selectivity, but the structural complexity of these devices puts a limit on their minimal size and cost.…”