Deconvolution of a three-component co-eluting peak cluster in gas chromatography-mass spectrometry

The GC-MS of a horse urine extract obtained 40 h after doping with quinine is analysed. An unresolved cluster of peaks is studied. Several problems oc cur specifically with GC-MS data, which are solved using chemometrics metho ds. The use of windows to select masses, with the diagnostic masses changin g according to window size and position, is discussed and used in calculati ons of derivatives to determine the composition of the chromatogram. PCA lo adings and scores plots are obtained. The use of deconvolution to obtain cl ean spectra of the metabolites together with pseudo-simulations for determi nation of underlying peak-shapes is described.