Fragment ion prediction method of compound and application

Abstract

The invention provides a fragment ion prediction method of a compound and application. The method comprises the following steps: 1) determining a compound for an experiment, a parent ion molecular formula of the compound and a fragment ion molecular formula of the compound; 2) selecting stable isotopes according to element composition of parent ions and fragment ions; 3) according to the determined compound, the molecular formula of the parent ion, the molecular formula of the fragment ion and the number of stable isotope elements in the parent ion and the fragment ion, calculating the condition that the parent ion and the fragment ion are labeled by the stable isotopes; 4) calculating the number of all parent ions and all fragment ions labeled by the stable isotopes; 5) according to the number of the marking conditions obtained in the step 4), calculating the accurate mass number of parent ions and fragment ions in all the marking conditions, and calculating the mass-to-charge ratio; and 6) establishing a mass-to-charge ratio database of fragment ions of the compound.

Description

technical field [0001] This application relates to the preprocessing of mass spectrometry data and the extraction method of effective information in isotope labeling experiments, in particular to a method for predicting, collecting and qualifying fragment ions of stable isotope-labeled compounds presented in mass spectrometry data. Background technique [0002] Chromatography-mass spectrometry combines the separation ability of chromatography with the qualitative function of mass spectrometry, so as to achieve quantitative and qualitative analysis of compounds in complex samples, and is the main tool for metabolomics analysis. Chromatographs coupled with mass spectrometers mainly include gas chromatography and liquid chromatography. Mass spectrometers mainly include quadrupole mass spectrometers, ion trap mass spectrometers, and time-of-flight mass spectrometers according to the analyzers. Medium-resolution and high-resolution mass spectrometers. The detection principle is ...

AI Technical Summary

Problems solved by technology

[0003] The mass numbers of precursor ions and fragment ions play a vital role in the identification of metabolites. When using chromatography-mass spectrometers to detect metabolic flux experiments, the experimental complexity lies in the fact that the labeling elements of different analytes are different, and the labeling of different analytes The position is different; when the same labeling element is used for different analytes, different labeling positions and labeling quantities will also result in completely different analyte targets; even for the same labeling compound, due to the complex metabolic network, the relationship between various metabolites Communication is complex and changeable, and the labeling of the same metabolite from different pathways is also different, which makes the labeling of target metabolites diverse; the structure of some analyte characteristic fragment ions is unknown, which further increases the association with isotope-labeled compounds Difficulty, especially for non-characteristic groups

The sources of metabolites are complex and diverse, and the labeling of fragment ions is complex and changeable, so there are cases where the metabolic relationship between the labeled compound and the analyte is not clear

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