| Title: | Effect of thermal desorption kinetics on vapor injection peak irregularities by a microscale gas chromatography preconcentrator |
| Author(s): | Seo JH; Liu J; Fan X; Kurabayashi K; |
| Address: | "Engineering Research Center for Wireless Integrated Microsensing and Systems, University of Michigan, Ann Arbor, Michigan 48109, USA" |
| ISSN/ISBN: | 1520-6882 (Electronic) 0003-2700 (Linking) |
| Abstract: | "Microscale gas chromatography (muGC) is an emerging analytical technique for in situ analysis and on-site monitoring of volatile organic compounds (VOCs) in moderately complex mixtures. One of the critical subcomponents in a muGC system is a microfabricated preconcentrator (mu-preconcentrator), which enables detection of compounds existing in indoor/ambient air at low (~sub ppb) concentrations by enhancing their signals. The prevailing notion is that elution peak broadening and tailing phenomena resulting from undesirable conditions of a microfabricated separation column (mu-column) are the primary sources of poor chromatographic resolution. However, previous experimental results indicate that the resolution degradation still remains observed for a mu-column integrated with other muGC subcomponents even after setting optimal separation conditions. In this work, we obtain the evidence that the unoptimized mu-preconcentrator vapor release/injection performance significantly contributes to decrease the fidelity of muGC analysis using our state-of-the-art passive preconcentrator microdevice. The vapor release/injection performance is highly affected by the kinetics of the thermal desorption of compounds trapped in the microdevice. Decreasing the heating rate by 20% from the optimal rate of 90 degrees Cs(-1) causes a 340% increase in peak tailing as well as 70% peak broadening (30% peak height reduction) to the microscale vapor injection process" |
| Keywords: | "*Chromatography, Gas Gases/*chemistry Kinetics Temperature Volatile Organic Compounds/analysis;" |
| Notes: | "MedlineSeo, Jung Hwan Liu, Jing Fan, Xudong Kurabayashi, Katsuo eng Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. 2012/07/12 Anal Chem. 2012 Aug 7; 84(15):6336-40. doi: 10.1021/ac300755d. Epub 2012 Jul 18" |
