Patent ID: 8884218

Claim:
A method for mass spectrometry for an identification and/or structural analysis of an unknown substance using a mass spectrometer capable of obtaining an MS n spectrum by performing an MS n analysis in which an ion originating from a substance to be analyzed is dissociated in n-1 stages (where n is an integer equal to or greater than two), comprising: a) a structural formula deduction step, in which a chemical structural formula of an unknown substance is deduced based on a molecular weight of the unknown substance determined from a mass spectrum obtained by performing a mass spectrometry of the unknown substance or on a composition formula deduced from the molecular weight; b) a dissociation state deduction step, in which a production to be detected in an MS n analysis of the unknown substance is deduced by predicting a dissociation pattern of an ion originating from the unknown substance based on the chemical structural formula deduced in the structural formula deduction step; and c) an evaluation step, in which a spectrum pattern formed by the product ion deduced in the dissociation state deduction step and an MS n spectrum obtained by performing an MS n analysis of the unknown substance are compared, and a degree of reliability of the deduction of the chemical structural formula by the structural formula deduction step is evaluated based on a similarity between the spectrum pattern and the MS n spectrum, wherein in the evaluation step, the spectrum pattern formed by the product ion based on a prediction of the dissociation pattern with an increased value of n and an MS n spectrum obtained by an actual MS n analysis are compared, and the evaluation of the reliability of a previously conducted deduction of the chemical structural formula is verified based on the similarity between the spectrum pattern and the MS n spectrum.