Real-time analysis of multicomponent chromatograms: application to high-performance liquid chromatography

Abstract

In liquid chromatography with photodiode array detection, a number of approaches have been developed in chemometrics to determine an analyte of interest in the presence of one or more unknown compounds. So far, these techniques have required time-consuming data analysis programs, and are not suitable for routine analysis. A ‘derivative spectrum chromatogram’ is proposed as a new approach for resolving overlapped peaks in real time. This procedure is based on the following assumptions: (i) an absorption spectrum of an analyte with rounded humps changes to steep peaks by high-order derivatization; and (ii) the principle of superposition is valid for the derivative spectra of a sample mixture. The performance of this procedure is assessed with real data for the separation of pesticides by liquid chromatography.