Issue 6, 1998

1-(2-Pyridylazo)-2-naphthol modified carbon paste electrode for trace cobalt(II) determination by differential pulse cathodic voltammetry

Abstract

A differential pulse cathodic voltammetric method was developed for the sensitive and selective determination of CoII at a 1-(2-pyridylazo)-2-naphthol modified carbon paste electrode. The analysis procedure consisted of an open circuit accumulation step in stirred sample solution. This was followed by medium exchange to a ‘clean’ solution where the accumulated CoII was oxidized and subsequently a cathodic potential scan was effected to obtain the voltammetric peak. The precisions obtained for 10 successive determinations each of 1.00 × 10–6 mol l–1, 1.00 × 10–7 mol l–1 and 1.00 × 10–8 mol l–1 CoII were 2.80, 5.14 and 9.67% (relative standard deviations), respectively. The detection limit was estimated to be 5.9 × 10–9 (0.35 ppb) (S/N = 3), for 180 s accumulation. Of the 35 selected substances examined for interferences, only VII, CeIII, EDTA and Triton X-100 interfered. These interferences could be easily eliminated. The developed method was tested using a certified sample (USEPA WP 386) and then applied to the determination of CoII in human hair, pig liver and spinach samples.

Article information

Article type
Paper

Analyst, 1998,123, 1351-1357

1-(2-Pyridylazo)-2-naphthol modified carbon paste electrode for trace cobalt(II) determination by differential pulse cathodic voltammetry

M. Rehana Khan, Analyst, 1998, 123, 1351 DOI: 10.1039/A707375E

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements