The ion/molecular reaction in ion trap mass spectrometer can induce the change of mass spectra, so using the mass spectra to match quadrupole mass spectral reference library can not give satisfactory results. A method was presented for extrating individual component spectra from full-scanning GC/ion trap MS data using principal component analysis. Mass spectra extracted by the method is immune to effects of ion/ molecular reaction and base noise. Compared to traditional method, the method is superior to match NIST 02 reference MS library by different matching methods.

Key words: principle component analysis, extraction of mass spectra, ion trap mass spectrometer