1P-44（1D-O1-1505） PDF
Physicochemical Prediction of MS/MS Spectra
The library of standard MS/MS spectra is currently not comprehensive despite its absolute necessity in metabolite identification from MS/MS information. Measuring standard spectra is not only complicated but also costly, and it is difficult to measure standard spectra for all metabolites. To expand the library, many groups have challenged to predict MS/MS spectra only from compound structures. Some of the successful examples were achieved by machine learning, but its accuracy does not help us to understand the mechanism of fragmentation.
We have analyzed physicochemical properties including energetic stability and electronic structures in metabolite fragmentation, by using computational chemistry. We have confirmed that energetically stable fragments are more likely to be produced in MS/MS and succeeded in distinguishing favorable and unfavorable fragmentation pathways according to their physicochemical properties.
In this study, we predict MS/MS spectra by physicochemical theories. The key quantity is the activation energy to break a chemical bond in compound structures. For each chemical bond, the two bound atoms and their adjacent chemical groups are taken into consideration. The activation energy to break the bonding pattern is calculated by a computational chemistry method. We will discuss the prediction of MS/MS spectra using the activation energy calculation.