| 摘要 |
<p>A method of mass spectrometry comprises separating precursor ions using an ion mobility separator 4 and mass filtering said separated precursor ions. The mass to charge ratios m/z of the precursor ions transmitted by the mass filter 6 is varied as a function of the drift times DT of the precursor ions through the ion mobility separator 4. The separated and mass filtered precursor ions are fragmented, and the fragment ions are urged through the fragmentation device 8 such that fragment ions derived from different precursor ions remain spatially separated, i.e. temporal fidelity of the ion mobility separation is maintained. The fragment ions are detected e.g. using a mass analyser 10. The method enables precursor ions to be associated with their related fragment ions more accurately by removing undesired precursor ions with similar drift times prior to fragmentation, as in MSE analysis. In alternative embodiments, mass filtering may be performed before separation and separation may be performed using field asymmetric ion mobility separation (FAIMS) or by other physic-chemical properties of the precursor ions.</p> |
