A micro gas chromatograph with integrated bi-directional pump for quantitative analyses

This paper describes a micro gas chromatography (μGC) system that comprises a Knudsen pump with bidirectional capability (KP2), a two-stage preconcentrator-focuser (PCF2) and a separation column. In this valveless system, the bi-directionality of the pump allows flow reversal in the multi-stage preconcentrator. The KP2, PCF2, and separation column are arranged in a 4.3 cm³ stack, and used with a commercial flame ionization detector. In preliminary experiments, the μGC system demonstrated quantitative separation of benzene, toluene, and xylene (BTX) in ambient room air.