Title: | Multi-adsorbent preconcentration/focusing module for portable-GC/microsensor-array analysis of complex vapor mixtures |
Address: | "Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI 48109-2029, USA" |
ISSN/ISBN: | 0003-2654 (Print) 0003-2654 (Linking) |
Abstract: | "A small multi-adsorbent preconcentration/focusing module for a portable GC with microsensor-array detector designed to determine complex mixtures of volatile and semi-volatile organic compounds encountered in indoor working environments is described. Candidate adsorbents were assessed on the basis of analyte thermal-desorption bandwidth and efficiency, chromatographic peak shape, and breakthrough volume against mixtures of organic compounds ranging over four orders of magnitude in vapor pressure. A capillary packed with just 12.3 mg of adsorbent material comprising Carbopack B (8 mg), Carbopack X (2.5 mg) and Carboxen 1000 (1.8 mg) provided the best tradeoff in operating variables, while maintaining sufficient capacity for a 1 L air sample containing a mixture of up to 43 compounds, each at 100 parts-per-billion, at an ambient relative humidity of up to 100%. On-column focusing and temperature programming were used to enhance chromatographic separations, and detection limits as low as 100 parts-per-trillion were achieved for a 1 L air sample using an integrated array of polymer-coated surface-acoustic-wave (SAW) sensors. Implications for field analysis of indoor air quality are emphasized" |
Keywords: | "Acoustics Adsorption Air Pollutants/*analysis Chromatography, Gas/instrumentation Environmental Monitoring/*instrumentation/methods Sensitivity and Specificity;" |
Notes: | "MedlineLu, Chia Jung Zellers, Edward T eng R01-OH03692/OH/NIOSH CDC HHS/ Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. England 2002/08/28 Analyst. 2002 Aug; 127(8):1061-8. doi: 10.1039/b111689d" |