Determination of antimony using forced-flow liquid chromatography with a coulometric detector

Abstract

The highly irreversible electrochemical oxidation of Sb(lll) at a platinum electrode in dilute HCI is electrocatalyzed by Ior l2 specifically adsorbed at the electrode surface. This phenomenon was applied for the determination of antimony in several standard alloys and in human hair by a highly sensitive and selective method using forced-flow liquid chromatography with a platinum coulometric detector. Because the electrolytic efficiency of the detector was 100%, the quantity of Sb(lll) in the samples was calculated directly from the integral of the current-time peak for Sb(lll) using Faraday's law. Use of a calibration curve was unnecessary.Johnson and Larochelle recently described a simple design for a tubular electrode (1). When packed with chips of platinum, the electrode can be operated with 100% electrolytic efficiency for a large range of fluid flow rates.

Chromatographic determination of chromium(VI) with coulometric detection based on the electrocatalysis by adsorbed iodine of the reduction at platinum electrodes in acidic solutions

“…Results of this work have convinced us that determinations of many species by this technique can be made with detection limits at the part-per-billion level or lower (3,5 ) . We report here the determination of Cr(V1) without interference from a large number of inorganic species including oxygen by liquid chromatography with coulometric detection.…”

“…We have been interested in the development of a general methodology for determining ionic species a t trace levels in complex aqueous samples based on liquid chromatographic separation with in-stream amperometric and coulometric detection (2)(3)(4)(5). Results of this work have convinced us that determinations of many species by this technique can be made with detection limits at the part-per-billion level or lower (3,5 ) .…”

“…trodes. Davenport and Johnson (15) reported the electrocatalysis of the irreversible oxidation of Sb(III) by adsorbed I and Taylor and Johnson (3) applied the electrocatalyzed reaction for determination of Sb(III) by liquid chromatography with coulometric detection. Lane and Hubbard (16) reported the electrocatalysis of the oxidation of ascorbic acid by adsorbed I at a Pt electrode.…”

Electrochemical Detection Methods for Monoamine Measurements in Vitro and in Vivo

“…With liquid chromatography systems, relatively slow separation conditions are required. This type of electrode has most commonly been used for detection of metal and other inorganic ions (e.g., Takata and Fujita, 1975;Taylor and Johnson, 1974).…”

Electrocatalytic detection of cobalt separated by ion exchange chromatography

“…A novel and sensitive electrocatalytic method for the detection of cobalt ion was found unexpectedly in the process of detecting ferrous ion by oxidation using a coulometric detector for liquid chromatography (1)(2)(3). A large peak appeared before the ferrous ion peak when the sample solution contained cobalt ion.…”