Basic Information
Abstract Number: 7000-600    
Author Name: Mark Libardoni Affiliation: University of Michigan
Session Title: Multidimensional Gas Chromatography
Event Type: Oral
Event Title: On-Line Multi-Bed Sorption Trap Coupled to a Portable Comprehensive Two-Dimensional Gas Chromatograph
Presider(s): Larive, Cynthia K Start Time: 03:25 PM ( Slot # 7 )
Date: 03/08/2004 Location: S505b
Keywords: GC, Environmental, Sample Introduction, Volatile Organic Compounds

Co-Authors
NameAffiliation
Sacks, Richard DUniversity of Michigan
Stevens, Peter TUniversity of Michigan

Abstract Content
Recent interest in complex multi-component analysis has led to the development of a portable comprehensive two-dimensional gas chromatograph (2DGC) that utilizes a multi-bed sorption preconcentrator as an injection system. This unique coupling allows for the analysis of complex air samples, trace level detection of atmospheric components and human breath analysis. The system platform consists of an on-line multi-bed sorption trap, two independently controlled columns with at-column heating, a resistively heated and air-cooled thermal modulator and a time of flight mass spectrometer detector. Human breath samples are collected in a 1.0 L sample bag. The breath samples are vacuum drawn through the preconcentrator at ambient temperature. The flow of the carrier gas is switched to a positive pressure and the trapped components are desorbed by resistive heating of the preconcentrator. Comprehensive 2DGC is carried out by means of a resistively heated and air cooled thermal modulator. The modulator is based on a single-stage air-cooled piece of wall coated metal capillary tubing that is rapidly heated for thermal desorption. A recirculating pump and a cryo-cooled gas exchanger provides rapid cooling for component trapping in the modulator. Eluting bands from the primary column are modulated over a three to five second period for rapid second dimension analysis. Spectral data from the second column effluent is acquired from a time of flight mass spectrometer and the resulting spectra are compared to a NIST library for identification. Component identification is also compared to previous studies using one-dimensional GC as well as 2DGC with a flame ionization detector.