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PubMed · 12195947

Multi-adsorbent preconcentration/focusing module for portable-GC/microsensor-array analysis of complex vapor mixtures.

Chia Jung Lu·Edward T Zellers
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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.

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AcousticsAdsorptionAir PollutantsChromatography, GasEnvironmental MonitoringSensitivity and SpecificityJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Chia Jung Lu, Edward T Zellers. 2002. Multi-adsorbent preconcentration/focusing module for portable-GC/microsensor-array analysis of complex vapor mixtures.. https://doi.org/10.1039/b111689d

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