Determination of componentwise chromatographic elution regions using singular value evolving profiles

A method to determine chromatographic elution regions for all components present in a sample using spectrochromatographic data is proposed. The method is essentially based on evolving spectral angles, i.e., angles between a base spectrum and spectra as they evolve over chromatograms. Because the angle is equivalent to the smallest singular value, corresponding singular value evolving profiles (SVEPs) can be used as well. The SVEPs were used in this study because SVEPs were found to more readily distinguish elution regions. All spectra from the spectrochromatogram act as a pseudoreference (base) spectrum and an SVEP is produced for each pseudo-reference spectrum. Examining SVEPs as they evolve over time allows componentwise elution regions to be determined. The method identifies elution regions without making any assumptions about the spectrochromatogram being analyzed.