The Use of a Solid Sampler in Chemical Ionization Mass Spectrometry for the Determination of Compounds Unstable Under Gas-Liquid Chromatographic Conditions-Analysis of Tolbutamide from Biological Fluid

Abstract

A simple method for the quantification of tolbutamide in biological fluids is presented. It is suggested that the method can be applied to some compounds that are unstable under gas liquid chromatographic conditions. The procedure is based upon the introduction of biological extracts into the ionization source of the mass spectrometer by means of a solid probe. Upon evaporation from the probe the compounds are subjected to high pressure chemical ionization with methane as a reactant gas. The abundant M + 1 ions that are formed are measured quantitatively with reference to deuterium substituted internal standard. Plasma concentrations of tolbutamide in rabbit following intravenous administration of 100 mg of tolbutamide is described.