| 摘要 |
In this mass spectrometry method, an ISD mass spectrum is searched for a pair of peaks having a mass-to-charge ratio difference corresponding to the mass obtained by subtracting 2[Da] from the mass of a matrix used in sample preparation (S6). In MALDI-ISD analysis wherein the analysis subject is a peptide, a z+Matrix* ion wherein a matrix radical is bonded to a z-ion resulting from the peptide is susceptible to being generated. In a case where the pair of peaks is present, therefore, it is determined that the peak having a smaller mass-to-charge ratio is assignable to the z-ion of the peptide (S7). The kinds of ions corresponding to some of many peaks are thus determined, whereby the accuracy of estimation of the sequence by database search or the like can be improved. Thus, the accuracy of identification of a peptide or a protein based on an ISD mass spectrum obtained by MALDI-ISD analysis can be improved. |
