METHOD FOR TANDEM MASS SPECTROMETRY ANALYSIS IN ION TRAP MASS ANALYZER

摘要

This invention is related to a tandem mass spectrometric analysis method in ion trap mass analyzer. Such method comprise three stages as represented by selective isolation, collision induced disassociation and mass scanning of ion. At the collision induced isolation stage, this invention is expected to endow parent ion of certain mass-charge ratio with energy through resonance excitation by changing cycle of radio frequency signals, namely frequency of radio frequency voltage imposed on the ion trap; such high-energy ions produced through resonance excitation are to be disassociated through collision with neutral molecules in the ion trap, which will further generate product ion to realize tandem mass spectrometric analysis. Advantage of this method lies in the fact that it can realize collision induced disassociation by changing scanning cycle at the stage of collision induced disassociation stage through software configuration, which can significantly simplify experimental devices and methods for tandem mass spectrometric analysis.

主权项

1. A tandem mass spectrometric analysis method in ion trap mass analyzer, comprising three stages as represented by selective isolation, collision induced disassociation and mass scanning of ion in proper sequence, wherein:
Selected parent ion is to be isolated at said stage of selective isolation of ion; whereas parent ion isolated is to be confined in the ion trap through collision with neutral gas molecules and cooling under the action of electric field produced by working voltage in ion trap; At said collision induced disassociation stage, cycle of ion excited radio frequency voltage signals imposed on the ion trap pole is changed to further change cycle of radio frequency voltage produced by resonance excitation of ion; as a result of it, ion of certain mass-charge ratio is to be provided with higher energy, subjecting to resonance excitation by ion excited radio frequency voltage of certain cycle or frequency; ion subjecting to resonance excitation is to be disassociated to generate fragment ion through collision with neutral molecules in ion trap; fragment ion subjecting to cooling in ion trap is to be confined for follow-up mass analysis; At said mass scanning and analysis stage, ion in ion trap is to subject to resonance excitation under the action of dipolar excitation voltage as imposed on the electrode of ion trap; eventually, it is to be discharged from lead-out hole or groove of ion extraction electrode to capture mass spectrometry signals, subjecting to detection on ion detector outside ion trap.