Determination of cadmium by electrothermal atomic absorption spectrometry using electrochemical separation in a microcell

Electrodeposition on the graphite electrode under conditions of controlled current in a flow-through mode, followed by electrothermal atomic absorption spectrometry, is proposed for the determination of cadmium. After electrolysis in a microcell of 2.6 μl volume, deposited metal was dissolved in 40 μl 0.2 mol l−1 HNO3 and the whole volume was direct injected into the atomizer. Using this on-line arrangement and electrodeposition from 1.75 ml of sample solution detection limit of 25 ng l−1 Cd was attained. The method was applied for the determination of cadmium in a real sample of seawater.