Separation and determination of metal ions as picolinaldehyde 4-phenyl-3-thiosemicarbazone chelates by reversed-phase high-performance liquid chromatography

Abstract

Picolinaldehyde 4-phenyl-3-thiosemicarbazone (PAPT) was used as a pre-column chelating reagent for the reversed-phase high-performance liquid chromatographic separation and determination of BiIII, CdII, CoII, CuII, NiII, and FeIII. The metal–PAPT chelates were separated on an ODS column with acetonitrile–water (50 + 46), containing 1.5% methanol, 2.5% pyridine, 7.5 × 10–5 mol dm–3 PAPT and 0.02 mol dm–3 acetate buffer (pH 6.0), as eluent. The detection limits for BiIII, CdII, CoII, NiII and FeIII were 3.0, 2.6, 0.6, 1.2 and 1.9 µg dm–3, respectively. The addition of pyridine to the eluent, as modifier, was effective in improving peak shapes. Nickel(II) in river water was determined by the proposed method.