Portable gas chromatograph with tunable retention and sensor array detection for determination of complex vapor mixtures

Chia-Jung Lu, Joshua Whiting, Richard D. Sacks, Edward T. Zellers

Research output: Contribution to journalArticle

110 Citations (Scopus)


A prototype portable gas chromatograph that combines a multiadsorbent preconcentrator/focuser, a tandem-column separation stage with individual column temperature control and junction point pressure modulation, and a detector consisting of an integrated array of polymercoated surface acoustic wave microsensors is described. Using scheduled first-column stop-flow intervals and independent temperature programming of the two columns, it is possible to adjust the retention of eluting analyte vapors to maximize vapor recognition with the microsensor array and minimize the time of analysis. A retention window approach is combined with Monte Carlo simulations to guide retention tuning requirements and facilitate pattern recognition analyses. The determination of a 30-vapor mixture of common indoor air contaminants in < 10 min is demonstrated using ambient air as the carrier gas. Detection limits of < 10 ppb are achieved for the majority of compounds from a 1-L air sample on the basis of the most sensitive sensor in the array. Performance is assessed in the context of near-real-time indoor air quality monitoring applications.

Original languageEnglish
Pages (from-to)1400-1409
Number of pages10
JournalAnalytical Chemistry
Issue number6
Publication statusPublished - 2003 Mar 15


ASJC Scopus subject areas

  • Analytical Chemistry

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