Separation of Metal Bis(2-hydroxyethyl)dithiocarbamate Complexes by Micellar Electrokinetic Capillary Chromatography

Abstract

A method was developed for the separation of Cd ^II , Pb ^II , Pt ^II , Co ^II , Ni ^II , Bi ^III , Cr ^II , Cu ^II and Hg ^II bis(2-hydroxyethyl)dithiocarbamate (HEDTC) complexes by micellar electrokinetic capillary chromatography. The complexes were formed by pre-capillary reaction of the metal ions with an excess of the ligand and then separated using a 100 mM borate buffer (pH 9.2) containing 4% methanol (v/v), 10 mM sodium dodecyl sulfate and 0.1 mM HEDTC, with detection at 254 nm. All the metal complexes, except Pt ^II and Pb ^II , were baseline resolved and separation was achieved in under 7 min. Detection limits were in the range 22 to 133 ppb.