UNIQUE RESOLUTION OF HIDDEN MINOR PEAKS IN MULTIDETECTION CHROMATOGRAPHY BY 1ST-ORDER DIFFERENTIATION AND ORTHOGONAL PROJECTIONS

A new method for unique resolution of multiwavelength chromatograms wi th a minor analyte completely overlapped by a major one in time direct ion and with no selective wavelength regions for any of the analytes i s derived in this paper. An orthogonal projection is first utilized to obtain the chromatographic profile of the minor analyte. Differentiat ion of the two-way data matrix in the time direction is subsequently p erformed to determine the retention time of the chromatographic peak m aximum of the major analyte. Based upon these two pieces of informatio n, two approaches for estimating spectra and chromatographic profiles of the pure analytes are developed. A direct approach, which assumes l ocal symmetry in the proximity of the chromatographic peak maximum of the major analyte, and an optimization approach using the estimated pe ak maximum of the major analyte as objective function.