MASS-SPECTROMETRIC STUDIES ON THE RESPONSE MECHANISM OF SURFACE-IONIZATION DETECTORS FOR GAS-CHROMATOGRAPHY

Mass spectrometric techniques at atmospheric pressure are used to measure the ionic species generated when organic compounds from a gas Chromatograph come into contact with a hot Pt emitter. The intensities and types of ions formed against surface temperature, gas environments around the emitter, and emitter material were investigated. in almost every sample studied, the observed ion species in the mass spectrum are the same as those obtained with SIOMS (surface ionization organic mass spectrometry in vacuum condition) with only the intensity distribution showing differences. The results confirm that positive surface ionization is the mechanism of the production of charge carriers in the surface ionization detector. © 1990, American Chemical Society. All rights reserved.