Patent ID: 8294086

Claim:
A method for acquiring daughter ion spectra in a time-of-flight mass spectrometer, with an ion source for ionization of analyte molecules by matrix-assisted laser desorption, with a parent ion selector, a post-acceleration unit, and a first ion detector, the method comprising: directing a single desorbing pulse of laser light onto a sample to generate analyte ions, and accelerating the analyte ions into an ion beam in an original flight direction; fragmenting the analyte ions from parent ions into daughter ions by one of either (i) collisional induced dissociation between a first acceleration of the analyte ions at the ion source and the post-acceleration unit, or (ii) post-source decomposition of metastable ions; multiply switching the parent ion selector following the single desorbing pulse of laser light to create a sequence of switching time windows and to select a plurality of species of the parent ions with the associated daughter ions in a time sequence one after another such that the daughter ion spectra do not show substantial overlap, wherein switching includes allowing one selected species of the parent ions with the associated daughter ions to pass in a straight line per switching time window; post-accelerating the selected species of the parent ions with the associated daughter ions in the original flight direction with the post-acceleration unit; and measuring the daughter ion spectra from the selected species of the parent ions separately in the ion detector by temporal sequencing the measurements.