1993 Volume 9 Issue 3 Pages 391-395
A probe-type insertion discharge electrode for Townsend discharge chemical ionization, which offers characteristic ionization, was developed to fit commercially available mass spectrometers. Studies on reactant ions formed from reagent gases (O2, NO, CH4) showed that the position of the electrode in the ion source, its insulation, and the applied voltage were of particular importance. Elements such as material, diameter and shape of the electrode were found to be of less significance. Mass spectra and peak profiles obtained by selected ion monitoring of standard compounds showed this probe-type electrode to be of practical value.
