Collect. Czech. Chem. Commun. 1988, 53, 1162-1171

The determination of Cu, Ni, and Co using 2-(2-pyridylazo)-1-naphtol-4-sulfonic acid by multicomponent flow injection analysis (MC-FIA)

Petr Doležel and Vlastimil Kubáň

Department of Analytical Chemistry, J. E. Purkyně University, 611 37 Brno


2-(2-Pyridylazo)-1-naphthol-4-sulfonic acid (1PAN4S) was used to develop a method for the simultaneous spectrophotometric determination of Cu(II), Ni(II), and Co(III) by reverse flow injection analysis (FIA) using a multichannel UV-VIS detector with a diode array. The method can be used to determine the individual ions in the range 5-50 μmol dm-3 Ni(II) or Cu(II) and 5-60 μmol dm-3 Co(III) in binary and ternary mixtures at ratios of 1 : 1 to 1 : 10 with a maximal relative deviation of units of per cent for the major components and tens of per cent for the minor components. The precision and accuracy of the determination are the same or slightly worse than for stationary measurements with half to one fifth the sensitivity. Measurement of the absorption spectra for the maximum analytical signal in digital form for c(1PAN4S) = 0·12 mmol dm-3, c(NaIO4) = 1·2 mmol dm-3 in 0·2M acetate buffer medium at pH 5·00 permits rapid determination (15 s per sample) of all the components using a simple program for multicomponent analysis in "overdetermined" systems.