ETAAS determination of lead with on-line preconcentration using a flow-through electrochemical microcell

An on-line electrodeposition method in a flow-through microcell of 3-mu L volume coupled to an electrothermal atomic absorption spectrometer (ETAAS) was del-eloped for the preconcentration and determination of lead. The method was used for the determination of ultratrace levels of lead in high purity reagents (NaCl, Na2SO4). The system offers the high efficiency of the deposition (over 70%) and dissolution in 40 mu L eluent. The determination is free from interference, since the analyte is separated from the bulk matrix. A detection limit (3 sigma) of 1.2 ng/L was achieved with a 3-minute preconcentration step, The relative standard deviation (n=12) was 4.6% at the 100-ng/L level.