Principal component analysis for the selection of variables in the application of the H-point and generalised H-point standard addition method

The present paper deals with the selection of variables for the H-point and generalised H-point standard additions methods (HPSAM and GHPSAM, respecti vely). Both methods are applied for the resolution of spectroscopic interfe red signals in the UV-vis range. The HPSAM is a suitable method for the res olution of binary and ternary mixtures when the interferent is known. The G HPSAM is applied for the resolution of samples that contain unknown interfe rents. In this paper, a method based on the study of a principal components analysis (PCA) for the selection of variables for the HPSAM and GHPSAM is proposed. The PCA results show the isolation of the analyte signal from the sample signal, achieved by the application of the HPSAM and GHPSAM. It is showed that by means of the score and loading plots, it is possible to sele ct the most appropriate variables without a priori establishing any conditi on. (C) 2000 Elsevier Science B.V. All rights reserved.