Use of chemometric factor analysis for chromatographic integration: application to diode-array high-performance liquid chromatography of mixtures of chlorophyll a degradation products

Abstract

Quantification errors of using the vertical divisor method for single wavelength chromatographic integration of closely eluting peaks are discussed. A new approach of using the chemometric factor analysis method, heuristic evolving latent projections, prior to integration is discussed, and typical single-wavelength errors in estimated integrals are less than 1% on simulated data. The method was applied to three mixtures of six closely eluting chlorophyll degradation products. Single-wavelength quantification is good, provided that the wavelengths chosen are close to the maxima of the peaks. Further improvements can be made by summing over all wavelengths. Finally, an approach to normalization of chromatographic integrals is discussed, which is particularly valuable when pure standards are not available.