Experimental designs in atomic absorption spectrometry: Application to theselenium determination

The optimisation of the determination of inorganic selenium by Hydride Gene ration/Quartz Furnace- Absorption Atomic Spectrometry was performed conside ring 12 operating parameters. The research of the influent factors was carr ied out from two experimental designs 2(4). Their realisation has allowed t he determination of the operating conditions of the hydridation (HCl concen tration and NaBH4 solution flow rate), the adjustment of the gas flow rates (He, O-2 and H-2) and consequently the control of the whole analytical pro cess. The optimized method for the determination of inorganic selenium has been found to be sensitive, repeatable and reliable with absolute detection limits lower than 2 ng and relative standard deviations evaluated from 6 d eterminations ranging from 3 to 6%.