The generalized H-point standard-additions method to determine analytes present in two different chemical forms in unknown matrix samples - Part I. General considerations

This paper shows how the generalized II-point standard-additions method (GH PSAM) can be used to obtain the total concentration or concentrations of di fferent chemical forms of an analyte when the matrix of the sample is compl etely unknown. The spectral regions where the interferent behaviour can be considered as linear are found and the analyte concentration free from bias error is estimated. This paper includes the already published features of the GHPSAM and a new modification of this method which allows the simultane ous determination of two chemical forms of an analyte in a sample.