FOURIER-ANALYSIS OF MULTICOMPONENT CHROMATOGRAMS - THEORY AND MODELS

On the basis of only the assumptions of the independence between peak heights and peak position and of stationary retention time distribution and under the hypothesis of constant peak shape, Fourier analysis is applied to analyze the structure of multicomponent chromatograms. In essence analysis is made of the properties of the chromatographic response covariance as a function of time distance and of Its Fourier transform which Is the power spectrum (PS). A general theoretical expression for the PS of the chromatogram is derived as a function of relative peak height dispersion, peak position distribution, and peak shape properties. The PS of the total chromatogram has the property of being proportional to the PS of a single-component peak. Detailed expressions for the PS and of the autocovariance function of chromatograms having different retention time distributions are presented and discussed. The PS of multicomponent chromatograms having Poissonlan retention time distribution Is found to be congruent to the PS of the single-component peak. A new way to obtain the statistical attributes of multicomponent chromatograms (i.e. retention time distribution type, number of components In the chromatogram and peak shape properties) Is thus emphasized. © 1990, American Chemical Society. All rights reserved.