A purge and trap integrated microGC platform for chemical identification in aqueous samples

Details

• Personal Author:
  Agah M ; Akbar M ; Narayanan S ; Restaino M
• Description:
  The majority of current micro-scale gas chromatography (microGC) 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 (microPE) chip and its integration with a micro-scale gas chromatography (microGC) system for the extraction and analysis of water organic compounds (WOCs) from aqueous samples. The 2 cm times 3 cm microPE 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 microPE chip. The outlets are assigned for draining water from the chip and for directing purged WOCs to the micro-thermal preconcentrator (microTPC). The trapped compounds are desorbed from the microTPC by resistive heating using the on-chip heater and temperature sensor, are separated by a 2 m long, 80 microm wide, and 250 microm deep polydimethylsiloxane (OV-1) coated microGC separation column, and are identified using a micro-thermal conductivity detector (microTCD) 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. [Description provided by NIOSH]
• Subjects:
  Chemistry Chromatography Electrical Equipment And Supplies Environmental Exposure Environmental Pollution Occupational Health Safety Temperature Water Purification
• Keywords:
  Analytical-instruments Analytical-methods Chemical-analysis Chemical-extraction Chromatographic-analysis Detectors Electronic-circuits Electronic-components Environmental-contamination Environmental-pollution Equipment-design Gas-chromatography Heat-conduction Organic-chemicals Organic-compounds Photoelectric-cells Sampling Thermal-properties Volatiles Water-analysis Water-sampling

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• ISSN:
  0003-2654
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  139
• Issue:
  13
• NIOSHTIC Number:
  nn:20046640
• Citation:
  Analyst 2014 Jul; 139(13):3384-3392
• Contact Point Address:
  Masoud Agah, VT MEMS Lab, Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA
• Email:
  agah@vt.edu
• CAS Registry Number:
  Chlorobenzene (CAS RN 108-90-7) ; Ethylbenzene (CAS RN 100-41-4) ; Tetrachloroethylene (CAS RN 127-18-4) ; Toluene (CAS RN 108-88-3)
• Federal Fiscal Year:
  2014
• Performing Organization:
  Virginia Polytechnic Institute and State University
• Peer Reviewed:
  True
• Start Date:
  20120701
• Source Full Name:
  Analyst
• End Date:
  20150630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:af3344a154489b840953f5e4ec7c5dfd6bfe4f6b8a81449d40166575e4a1b43e98ec1debe60988049c751530c0533702556b936d53f8656e352324afd1aa0ed6
• Download URL:
  https://stacks.cdc.gov/view/cdc/201635/cdc_201635_DS1.pdf
• File Type:
  [PDF - 967.04 KB ]