Energy normalization and prediction of MS/MS library for small molecule identification

Abstract

A strategy for energy normalization in setting up MS/MS library for small molecule identification using a triple-quadrupole mass spectrometer was analyzed. The feasibility to predict MS/MS spectra using ab initio or DFT methods in combination with RRKM calculations was predicted. Product ion spectra of the model compounds were measured at different collision energies, collision gas (N 2) pressures and orifice voltages. It was shown that product ion spectra of a compound are reproducible, if they are acquired from precursor ions that have identical internal energy. The results show that the ability to determine the fragmentation pattern and generalize the energy-deposition function determine the utility of the approach.