Tandem mass spectrometer and mass spectrometric method

Abstract

An ion trap (5) is provided between a collision cell (3) and a time-of-flight mass separator (6). During a time period in which precursor ions derived from the same compound are selected with a quadrupole mass filter (2), a collision energy is changed from one to another. Various product ions that are produced by dissociation respectively under collision energies of the plurality of stages and precursor ions that are not dissociated are temporarily trapped in the ion trap (5), and are ejected in a packet form in the state where these ions are mixed, and are introduced into the time-of-flight mass separator (6) to be subjected to a mass spectrometry. Thereby, in a data processing unit (21), one MS / MS spectrum in which product ions produced in various dissociation modes under various CID conditions appear is created.

Description

Technical field [0001] The present invention relates to a tandem mass spectrometer and its mass spectrometry method. The tandem mass spectrometer dissociates ions with a specific mass-to-charge ratio by collision-induced dissociation (CID) or other methods, and performs the dissociation Mass spectrometry analysis of the produced product ions (fragment ions). Background technique [0002] In order to identify substances with larger molecular weights and analyze the structure of the substances, MS / MS analysis (or tandem analysis) is known as a method in mass spectrometry. In MS / MS analysis, ions with a specific mass-to-charge ratio among a plurality of ions generated from a sample are selected as precursor ions (ie, first-stage mass separation). Through some methods, precursor ions are Dissociation, these methods include a method in which precursor ions are exposed to CID gas, and various product ions produced by dissociation are separated according to their mass-to-charge ratios ...

AI Technical Summary

Problems solved by technology

[0006] However, in the mass spectrometer described in Patent Document 1, only two types of information of a highly split mass spectrum and a less split mass spectrum can be obtained, and the mass spectrometer is not always sufficient for analyzing compounds with complex molecular structures. structure

While it is possible to modify the mass spectrometer described in Reference 1 to obtain more than three MS / MS spectra using different CID conditions, it takes some time to perform mass spectrometry for a range of mass-to-charge ratios, and therefore, in The time required to acquire multiple MS / MS spectra for a compound under different CID conditions is correspondingly longer

[0007] Specifically, when a gas chromatograph (GC) and a liquid chromatograph (LC) are connected to the front stage of the mass spectrometer, and compounds temporarily separated by the chromatograph are analyzed by the mass spectrometer, one of the compounds is introduced into the mass spectrometer's The time width is significantly limited

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