Generalised H-point standard addition method for the isolation of the analyte signal from the sample signal when coelution of unknown compounds occurs in liquid chromatography

The generalised H-point standard addition method (GHPSAM) is proposed for i solating the analytical signal of an analyte from the signal of an unknown sample. Samples containing two and three coeluting compounds have been anal ysed. The accuracy of the predictions depends on the shape of the analyte a nd interferent spectra but not on the degree of chromatographic overlap. Th is methodology involves the location of linear intervals for the unknown in terference spectrum from the spectrum of the sample. Once the linear interv al has been found the selection of three wavelengths within the interval wi ll allow the cancellation of the signal of the unknown: interferent. The me thod has been applied to the determination of diuretics, amphetamines and p henols in water. (C) 1999 Elsevier Science B.V. All rights reserved.