Multicomponent analysis by flow injection using a partial least-squares model. Determination of copper and zinc in serum and metal alloys

Abstract

A partial least-squares multivariate calibration method for the resolution of mixtures of metal ions from the spectra of the complexes produced in a flow injection (FI) system has been developed. The method has been applied to the simultaneous determination of Cu^II and Zn^II with 4-(4′-methyl-2′-thiazolylazo)-2-methylresorcinol. The reagent exhibits a high absorbance and its spectrum strongly overlaps with the spectra of the complexes that it forms with copper and zinc ions. Chemical and FI variables influencing the system have been optimized and the proposed method validated on the determination of Cu and Zn in blood serum and metal alloys.