Determination of trace cadmium in environmental water samples using ion-interaction reversed-phase liquid chromatography with fluorescence detection.
An ion-interaction reversed-phase liquid chromatographic method has been developed for the determination of cadmium at low microg/l concentrations in environmental water samples. Cadmium and other matrix metals were separated through on-column complexation with 8-hydroxyquinoline sulphonate, using an octadecylsilica column and a mobile phase containing 15% acetonitrile, 10-13 mM tetrabutylammonium hydroxide, 5 mM 8-hydroxyquinoline 5-sulphonic acid and 10 mM acetic acid-acetate buffer (pH 4.8-5.4). Under the above conditions Cd(II) could be easily resolved from excess concentrations of matrix metals and could be detected at concentrations as low as 2 microg/l using fluorescence detection at 500 nm (based upon a 100-microl injection). The method showed a slightly curved detector response over the range of interest [up to 1 mg/l Cd(II)] and was successfully applied to the determination of trace Cd(II) in water samples containing large excesses of Mg(II) and Zn(II) and other matrix metals.
Paull
B
B
Analytical Separations Group, School of Chemical Sciences, Dublin City University, Ireland.
Twohill
E
E
Bashir
W
W
D002104:Cadmium / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods*; D013050:Spectrometry, Fluorescence; D014131:Trace Elements / Q000032:analysis*; D014867:Water / Q000032:analysis*
D014131:Trace Elements; D002104:Cadmium; D014867:Water