DETERMINATION OF RARE-EARTH ELEMENTS IN WINE BY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY USING A MICROCONCENTRIC NEBULIZER

A method for the direct determination of REEs in undiluted wine by ICP -MS was developed. The performance of a microconcentric nebulizer (MCN ) was optimized regarding the nebulizer gas how rate and sample uptake rate for all the REEs in terms of signal intensity and signal-to-nois e ratio. The effect of ethanol on the sensitivity was also studied Pos sible spectral interferences were identified and are discussed in deta il. The MCN was shown to reduce the sample consumption to 30-50 mu l m in(-1) and to decrease the matrix signal suppression by a factor of 2- 5 in comparison with a de Galan nebulizer. Polyatomic interferences we re found to be negligible except for those of BaO on Eu-151, Eu-153 an d Gd-155 and of (LaO)-La-139-O-16 on Gd-155. Data obtained with three different ICP-RIS instruments were compared. Several wines from differ ent vineyards in France, California and Australia were analysed for RE Es. The REE concentration patterns showed inter-continental and inter- regional variations, whereas no difference was observed for different vintages from the same vineyard over a period of several years.