Development of an Atmospheric Pressure Glow Discharge Detector for Capillary Column Gas Chromatography

Abstract.

 The use of the change in the oscillation frequency of the current of a new atmospheric helium glow discharge for sensitive signal detection for gas chromatography is studied. The effluent of a capillary column is directed into the glow discharge cell perpendicular to the axis of the glow discharge that existed between a platinum anode and cathode. A stable discharge is obtained when several hundred volts are applied between the 0.2-mm gap between the anode and cathode. The effects of the electrode gap, discharge voltage and gas flow rate on the baseline frequency and discharge current were investigated. The chromatogram shows that the discharge current and discharge gap have a strong influence on the detector response. The discharge current shows positive peaks; however, frequency peaks are positive or negative depending on the discharge conditions. The response of the detector is in the femto-mole and pico-mole range for nonane and decane.