Integrated qualitative analysis of fatty acid methyl esters (FAMEs) by msFineAnalysis iQ
MSTips No. 358
Electron Ionization (EI) used in gas chromatograph / mass spectrometer is one of a hard ionization method which tends to generate fragment ions. Compounds can be identified by comparing the mass spectra acquired by EI with libraries. On the other hands, soft ionization such as photoionization (PI) is used to find the molecular ion. Comparing the molecular weights of the compounds identified in the library with the molecular ions enables highly accurate qualitative analysis. Therefore we have developed an integrated qualitative analysis software called msFineAnalysis iQ. Fatty acid methyl esters (FAMEs) are important compounds for measuring the amount of lipids in food, and are used as biodiesel fuels due to their low environmental impact. Numerous unsaturated compounds with a double bond in the alkyl chain are contained in FAMEs. As the number of the double bonds increases, it tends to become more difficult to detect their molecular ions by EI. Therefore FAMEs standard sample was measured by EI and PI to confirm the detection of molecular ions. We report the results of the integrated qualitative analysis combining library database search and molecular ion confirmation when performing msFineAnalysis iQ.