Exploiting the Lab-on-Valve Concept for Determination of Trace Levels of Metals in Complex Matrices with Detection by ETAAS and ICPMS

Termed the third generation of flow injection analysis, the Sequential Injection (SI)-Lab-on-Valve (LOV) concept has proven to entail specific advantages and to allow novel and unique applications. Both in term of its use in the automation and micro-miniaturization of suitable on-line sample pretreatments such as separation of the analyte from potentially interfering matrix constituents and preconcentration in order to bring the concentration of the analyte into the dynamic measuring range of the detection device applied, and also as a versatile front end to a variety of detection techniques. Following a brief introduction into the characteristics of the SI-LOV approach, special emphasis is placed on its utilisation in conjunction with the bead injection scheme for on-line separation and preconcentration of ultra-trace levels of metals in complex matrices by exploiting the renewable microcolumn approach [1,2]. Coupled to detection by ETAAS and ICPMS, and illustrated by recent exploits in the authors’ laboratory, it is shown that this methodology eliminates the problems encountered in conventional on-line column preconcentration systems and at the same time improves the overall operational efficiency and yields the robustness necessary for use in routine assays. References 1. J.-H. Wang, E. H. Hansen, J. Anal. At. Spectrom., 16 (2001) 1349. 2. J.-H. Wang, E. H. Hansen, Anal. Chim. Acta, 467 (2002) 3.