Multiple-stage microfabricated preconcentrator-focuser for micro gas chromatography system.
Tian-W-C; Chan-HKL; Lu-C-J; Pang-SW; Zeller-ET
J Microelectromechanical Syst 2005 Jun; 14(3):498-507
The design, fabrication, and characterization of a multiple-stage Si microfabricated preconcentrator-focuser (µPCF) for a micro gas chromatography (µGC) system that can provide real-time quantification and identification of complex organic vapor mixtures are presented. The µPCF consists of a Si microheater loaded with Carbopack B, Carbopack X, and Carboxen 1000 carbon adsorbent granules, and a Si micromachined cover plate. Deep reactive ion etching is utilized to produce mechanically robust fluidic interconnection adapters hermetically sealed to fused silica capillary tubing for connection to the other components in the µGC. This three-stage device is designed to capture compounds spanning up to 4 orders of magnitude in volatility. The dead volume, thermal mass, heating efficiency, and pressure drop of the three-stage µPCF are improved significantly over its single-stage µPCF predecessor. We demonstrate the successful capture, desorption, and high-resolution chromatographic separation of a mixture of 30 common organic vapors using our three-stage µPCF in a conventional GC system. The peak width at half height is <2.05 s for all compounds after elution from the GC column.
Gas-chromatography; Organic-compounds; Organic-vapors; Vapors; Thermal-reactions; Chromatographic-analysis; Analytical-processes
Journal of Microelectromechanical Systems
University of Michigan, Ann Arbor