Implementation of suitable flow injection/sequential-sample separation/preconcentration schemes for determination of trace metal concentrations using detection by electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry

Various preconditioning procedures encomprising appropriate separation/preconcentration schemes in order to obtain optimal sensitivity and selectivity characteristics when using electrothermal atomic absorption spectrometry (ETAAS) and inductively coupled plasma mass spectrometry (ICPMS) are presented and discussed. Demonstrating that such pretreatments advantageously are to be performed in flow injection (FI) or sequential injection (SI) manifolds, where all appropriate unit operations can be effected under enclosed and strictly controlled conditions, procedures based on ion-exchange, precipitation/coprecipitation, adsorption, liquid-liquid extraction, extraction/back-extraction and hydride generation are reviewed. Emphasising the use of SI-systems, special attention is paid to the use of the newly introduced approach termed the lab-on-valve (LOV), where all necessary manipulations required prior to detection are effected in a microconduit placed on top of an SI selection valve.