Determination of trace tin in flow systems at an epoxy–carbon powder–8-hydroxyquinoline composite electrode

Abstract

An epoxy-carbon powder composite electrode bulk modified with 8-hydroxyquinoline was fabricated for the continuous flow and flow injection anodic differential pulse voltammetric determinations of Sn(II) after open circuit preconcentration. Factors affecting Sn(II) determination were systematically investigated and an optimized procedure was developed. Under the optimized conditions for the continuous flow system with 10 min accumulation, the calibration plot was linear from 5.00 3 10 29 to 1.00 3 10 26 M and a detection limit of 4.6 3 10 210 M (0.055 ppb, S/N = 3) was found. For six consecutive differential pulse stripping experiments each of Sn(II) concentrations of 5.00 3 10 29 , 5.00 3 10 28 and 5.00 3 10 27 M (10 min accumulations), relative standard deviations of 9.68, 7.45 and 3.38%, respectively, were obtained. For the flow injection mode, a detection limit of 5.4 ng (500 ml injection of 0.91 3 10 28 M, S/N = 3) was achieved. Selected metal ions and other substances were investigated for interferences. The developed method was tested with a spiked United States Environmental Protection Agency water quality control sample (USEPA WP 386) and then applied to the determinations of tin in human hair, canned fruit juice and spiked sea-water samples.

Electroanalytical Flow Measurements

“…Such a procedure has been applied for the determination of tin in flow systems at an epoxy-carbon powder / 8-hydroxyquinoline composite electrode with anodic differential pulse voltammetry after open circuit preconcentration. 25 For flow voltammetry also a special micro cell was developed with a Hgcoated iridium microelectrode combined with a hollow fiber supported liquid membrane that allows trace metal analysis without sample pretreatment. 26,27 A differential pulse voltammetry in flow system was reported for determination of trace Te(IV) at a poly(3,3'-diaminobenzidine) modified gold electrode.…”

Quinoline-8-ol and Its Derivatives as Preconcentration Agents in Flow Injection Analysis Coupled to Atomic and Molecular Spectrometric Techniques

“…49 With a 10 min accumulation time, the calibration plot was linear from 5 × 10 -9 to 1 × 10 -6 M with a detection limit of 0.055 ppb, corresponding to an SNR value of 3. The developed procedure was applied to the determination of tin(II) in human hair, canned fruit juice and spiked seawater samples.…”

Reductive spectrophotometry of divalent tin sensitization on soda lime glass

“…Spectrometric [15][16][17] and electrochemical [18][19][20] methods have been used to quantitate tin (II) in solutions. But they have not been applied to quantitate the mass of tin (II) deposited on substrates to sensitize EL plating.…”