ONLINE PRECONCENTRATION SYSTEM FOR LANTHANUM DETERMINATION IN URINE USING FI-ICP-AES

An on-line lanthanum preconcentration and determination system impleme nted with inductively coupled plasma-atomic emission spectrometry (ICP -AES) associated to flow injection (FI) method was studied. For the re tention of lanthanum, quinolin-8-ol and Amberlite XAD-7 were used at p H 9.5. The lanthanum complex was removed from the micro-column with ni tric acid. The value of detection limit for the preconcentration of 10 0 mi of aqueous solution was 0.09 ng ml(-1) with a relative standard d eviation (RSD) of 1.5%, calculated with the peak heights obtained. The calibration graph using the preconcentration system for lanthanum was linear with a correlation coefficient of 0.9993 at levels near the de tection limits up to at least 100 ng ml(-1). The method was successful ly applied to the determination of lanthanum in urine samples. (C) 199 8 Elsevier Science B.V.