Electrochemical detection of cobalt in hair following on-column derivatization with 1-(2-pyridylazo)-2-naphthol-6-sulphonic acid and reversed-phase liquid chromatography.

Journal Article (Journal Article)

A method for the specific determination of cobalt based on reversed-phase liquid chromatography with amperometric detection via on-column complex formation has been developed. A water-soluble chelating agent, 1-(2-pyridylazo)-2-naphthol-6-sulphonic acid (PAN-6S), is added to the mobile phase and aqueous cobalt solutions are injected directly into the column to form in situ the cobalt-PAN-6S chelate, which is then separated from other metal PAN-6S chelates and subjected to reductive amperometric detection at a moderate potential of -0.3 V. Because the procedure eliminates the interference of oxygen and depresses the electrochemical reduction of the mobile phase-containing ligand PAN-6S, by virtue of the quasi-reversible electrode process of the cobalt-PAN-6S complex, a low detection limit of 0.06 ng can be readily obtained. Interference effects were examined for sixteen common metal species, and at a 5- to 8000-fold excess by mass no obvious interference was observed. The feasibility of the method as an approach to the specific analysis of cobalt in a hair sample has been demonstrated.

Full Text

Duke Authors

Cited Authors

  • Zhou, J; Zhang, L; Wang, E

Published Date

  • September 8, 1993

Published In

  • J Chromatogr

Volume / Issue

  • 619 / 1

Start / End Page

  • 103 - 109

PubMed ID

  • 8245147

Digital Object Identifier (DOI)

  • 10.1016/0378-4347(93)80451-9


  • eng

Conference Location

  • Netherlands