| Title: | A purge and trap integrated microGC platform for chemical identification in aqueous samples |
| Author(s): | Akbar M; Narayanan S; Restaino M; Agah M; |
| Address: | "VT MEMS Lab, Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA. agah@vt.edu" |
| ISSN/ISBN: | 1364-5528 (Electronic) 0003-2654 (Linking) |
| Abstract: | "The majority of current micro-scale gas chromatography (muGC) systems focus on air sampling to detect volatile organic compounds (VOCs). However, purging the VOCs from a water sample using microsystems is an unchartered territory. Various organic compounds used in everyday life find their way to water bodies. Some of these water organic compounds (WOCs) persist or degrade slowly, threatening not just human existence but also aquatic life. This article reports the first micro-purge extractor (muPE) chip and its integration with a micro-scale gas chromatography (muGC) system for the extraction and analysis of water organic compounds (WOCs) from aqueous samples. The 2 cm x 3 cm muPE chip contains two inlet and outlet ports and an etched cavity sealed with a Pyrex cover. The aqueous sample is introduced from the top inlet port while a pure inert gas is supplied from the side inlet to purge WOCs from the muPE chip. The outlets are assigned for draining water from the chip and for directing purged WOCs to the micro-thermal preconcentrator (muTPC). The trapped compounds are desorbed from the muTPC by resistive heating using the on-chip heater and temperature sensor, are separated by a 2 m long, 80 mum wide, and 250 mum deep polydimethylsiloxane (OV-1) coated muGC separation column, and are identified using a micro-thermal conductivity detector (muTCD) monolithically integrated with the column. Our experiments indicate that the combined system is capable of providing rapid chromatographic separation (<1.5 min) for quaternary WOCs namely toluene, tetrachloroethylene (PCE), chlorobenzene and ethylbenzene with a minimum detection concentration of 500 parts-per-billion (ppb) in aqueous samples. The proposed method is a promising development towards the future realization of a miniaturized system for sensitive, on-site and real-time field analysis of organic contaminants in water" |
| Keywords: | "Chemical Fractionation/*instrumentation Chromatography, Gas/*instrumentation Equipment Design Volatile Organic Compounds/*analysis Water/*analysis Water Pollutants, Chemical/*analysis;" |
| Notes: | "MedlineAkbar, Muhammad Narayanan, Shree Restaino, Michael Agah, Masoud eng 5R21OH010330/OH/NIOSH CDC HHS/ Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. England 2014/05/20 Analyst. 2014 Jul 7; 139(13):3384-92. doi: 10.1039/c4an00254g" |
