Pulsed Mass Calibration in Time-of-Flight Mass Spectrometry

摘要

A method is provided for calibrating mass-to-charge ratio measurements obtained from a time-of-flight mass spectrometer used as a detector for a chromatographic system. The method can include introducing a calibrant material into the time-of-flight mass spectrometer after a sample is introduced to the chromatographic system, but before the analysis of the sample is complete, such that calibrant material and sample material are not present at the ion source of the mass spectrometer, contemporaneously, and back-flushing residual or leaking calibrant through a back-flush line and away from the mass spectrometer.

主权项

1. A method of calibrating mass-to-charge ratio measurements obtained from a mass spectrometer disposed in series, and in fluid communication with, a chromatographic system, the method comprising:
i) introducing a calibrant material into a mass spectrometer during an analytical run, the mass spectrometer comprising an ion source and the introducing occurring after a sample is introduced to a chromatographic system for the analytical run but before analysis of the sample is complete, the introducing being carried out such that calibrant material and sample material are substantially not present contemporaneously at the ion source of the mass spectrometer; ii) acquiring a multiplicity of mass spectra of the calibrant material during the analytical run; iii) calculating a multiplicity of mass calibrations on the basis of mass spectra obtained from the calibrant material introduced during the analytical run; and iv) back-flushing residual or leaking calibrant through a back-flush line and away from the mass spectrometer.