Deconvolution of overlapping chromatographic peaks by means of fast Fourier and hartley transforms

Abstract

Chromatographic peaks usually exhibit an exponentially Gaussian modified peak profile that is characterized by a tailing behaviour at the end of the peaks. As a result of this modification of the ideal peak shape, the peaks lose their symmetry and, most importantly, become broader. An unfortunate consequence of this broadening effect is that the resolution between adjacent peaks decreases as compared to the ideal case in which purely Gaussian symmetrical peaks would be considered. In addition to various chemometrical techniques developed to increase the separation of overlapping peaks, methods based on deconvolution in the frequency domain can be exploited. The principle of this latter family of deconvolution methods rests on the division of the frequency spectrum of the signal to be deconvoluted by the frequency spectrum of a judiciously chosen deconvoluting signal. In this paper, the analytical characteristics and utility of deconvolution is assessed with emphasis on aspects of resolution enhancement, data distortion, linearity and signal-to-noise ratios.