Sequential extraction of mass spectra and chromatographic profiles from overlapping gas chromatography-mass spectroscopy signals.

For resolution of multicomponent overlapping GC/MS signals, a window independent component analysis (WICA) is proposed. In WICA, the window information, i.e., the existing interval along the retention time, of each component is obtained. Then, with the data in the selective (non-overlapping) window, the mass spectrum of the first component is extracted by using independent component analysis (ICA), and with the data of selective (non-overlapping) ions, chromatographic profile of the component is calculated. With a subtraction of the extracted information from the data matrix, the information of the next component can be obtained. In this way, mass spectrum and chromatographic profile of each component can be extracted sequentially along the retention time. Due to the usage of the window information, the limitation of ICA in resolution of multicomponent overlapping analytical signals is overcome. Two experimental GC/MS data are analyzed with the proposed WICA. Results show that both mass spectra and chromatographic profiles of the components in the overlapping GC/MS signal are accurately extracted.