Studies with a laboratory-constructed thermospray liquid chromatograph-mass spectrometer interface

Abstract

The influence of a series of “thermospray electrolytes” (ammonium acetate, chloride, bromide and iodide and potassium acetate) on the characteristic mass spectra of saccharides diquaternary ammonium salts was investigated with a laboratory-constructed thermospray (TSP) liquid chromatograph-mass spectrometer interface. The observed dependence of mass spectral fragmentation and total ion current on the concentration and thermal stability, or temperature of volatilization, of TSP electrolytes indicates a significant role for solid particles in TSP ionization. The observed fragmentation is suggested to be related to the formation and decomposition of solid particles and to ion chemistry in the desolvation of molecules rather than to a “purely” thermal effect. A strong influence of the thermospray operating temperature on the relative fragment ion intensities could only be observed for diazo dyes.