Mass Identified Mobility Spectra of p-Nitrophenol and Reactant Ions in Plasma Chromatography

An interfaced plasma chromatograph/mass spectrometer (ALPHA-II) permits Identification of the positlve and negative ionic specles associated with ionlc peaks In the plasma chromatographic mobility spectra of pnitrophenol. The posltive ions observed and their reduced mobility values (KO) are MNO+ (1.67), MH+ (1.80) and the negative ion is [M HIat (1.87). These are essentially the ions that are predicted from chemical ionization mass spectrometry princlples and mobility data alone. An ion observed at mass 108 (KO 1.91) results from a thermal decomposition product of pnitrophenol. The major reactant ions were found at m/e 18, 30, 37, and 65, with probable structures of NH4+, NO', (H20)*H+and ( H20)2N2H+. The 37 and 65 ions occur at the same mobility. Comparison of reduced mobllity values, KO, between two independent laboratories gives an agreement within experimental reproducibility of f0.02 for these spectra.