| 主权项 |
1. A system for identifying precursor ions of product ions from combined product ion spectra produced by a tandem mass spectrometer that performs multiplexed precursor ion selection, comprising:
an ion source that provides a continuous beam of ions; a tandem mass spectrometer that includes a mass filter that performs multiplexed precursor ion selection; and a processor in communication with the ion source and the tandem mass spectrometer that selects N precursor ions,
creates N groups of the N precursor ions, wherein each of the N groups has N−1 precursor ions of the N precursor ions and wherein a different precursor ion of the N precursor ions is not included in each of the N groups,instructs the tandem mass spectrometer to perform multiplexed precursor ion selection on the continuous beam of ions for each of the N groups, fragment each of the N−1 precursor ions selected in each of the N groups, and measure the intensities of the product ions produced by each of the N groups, producing N product ion spectra,plots a heat map for each of the N product ion spectra, producing N heat maps,combines the N product ion spectra into a combined product ion spectrum, andidentifies a corresponding precursor ion of a peak in the combined product ion spectrum by finding a heat map of the N heat maps that does not have data for the mass of the peak and determining that a precursor ion of the N precursor ions that is not included in a group that produced the heat map is the corresponding precursor ion. |
