Selected ion monitoring mass spectrometry: Parameters affecting quantitative determination

Abstract

Instrumental parameters and possible correction procedures for hydrogen-transfer phenomena are studied, with emphasis on the improvement of quantitative measurements in selected ion monitoring mass spectrometry. The intensity ratio of the m/z 387 and 386 ions, derived from cholesterol, are measured by an HP-5995 mass spectrometer using different parameters, including calibration peak width, mass filter window size and ion monitoring dwell time. The intrinsic ratio of these two ions is calculated with a correction procedure accounting for the [MH]+ and [M2H]+ hydrogen-transfer phenomena.