A micro packed preconcentrator using ionic liquid coated graphitized carbons for detection of low concentration isoprene. (1st May 2023)

• Record Type: Journal Article
• Authors: Wu, Xinyu; Wang, Dazuo; Zhang, Kangning; Hua, Xinyuan; Wang, Hairong; Sun, Jianhai
• Is Part Of: Journal of micromechanics and microengineering. Volume 33:Number 5(2023)
• Publication Date: 2023-05-01
• Subjects: micro preconcentrator -- MEMS -- VOCs adsorbent -- ionic liquid -- isoprene; Microelectromechanical systems -- Periodicals; Micromechanics -- Periodicals; 621.38105
• DOI: 10.1088/1361-6439/acca2c
• Languages: English
• ISSNs: 0960-1317

Abstract

Abstract: Analysis of volatile organic compounds in the human exhaled mixture is a promising disease screening approach, and isoprene is a typical biomarker for nonalcoholic fatty liver disease in breath diagnosis. However, accurate detection of trace isoprene (ppb) is difficult due to the interfering effect of various gas sensors. In this study, we developed an integrated silicon-based micro preconcentrator (micro-PC) as a pretreatment component of the portable gas chromatography (GC) system. The device was the structure of parallel micro channels with flat dimensions of 20 mm × 10 mm on the silicon substrate, and the total internal empty volume is about 18 μ l. The micro electro mechanical system processes were used to fabricate the micro channels and the heating and temperature measuring resistances. The preconcentrator was filled with graphitized carbons with ionic liquids coating as an adsorbent. In the experiments, a GC equipped with a flame ionization detector was used to characterize the preconcentration performance. The micro-PC has a preconcentration factor (PF) value up to 49.8 for 100 ppb isoprene in 5 min adsorption time. Under the same conditions, the PF value of micro-PC using the modified adsorbent was 3.3 times higher than that using the commercial functional material. Besides, the fabricated preconcentrator had excellent desorption efficiency and good humidity resistance. These results indicated that the micro-PC we developed had a potential application in the micro GC system for non-invasive screening of chronic liver related diseases by detecting the trace isoprene.