On-line complexation/preconcentration system for the determination of lead in wine by inductively coupled plasma atomic emission spectrometry with ultrasonic nebulization

WUILLOUD, RODOLFO G.; GONZÁLEZ, A.; MARCHEVSKY, E.; OLSINA, ROBERTO A.; MARTINEZ, LUIS D.

JOURNAL OF AOAC INTERNATIONAL

AOAC INTERNATIONAL

Año: 2001 vol. 84 p. 1555 - 1560

1060-3271

An on-line lead preconcentration and determination system implemented with inductively coupled plasma-atomic emission spectrometry (ICP-AES) with ultrasonic nebulization (USN) in association with flow injection was studied. For the preconcentration of lead, a Pb-quinolin-8-ol complex was formed on-line at pH 6.8 and retained on Amberlite XAD-16 resin. The lead was removed from the microcolumn by countercurrent elution with nitric acid. A total enhancement factor of 225 was obtained with respect to ICP-AES with pneu matic nebulization (15.0 for USN and 15.0 for the column). The detection limit for Pb for the preconcentration of a 10 mL wine sample was 0.15 ?g/L. The precision for 10 replicate determinations at a Pb level of 25 ?g/L was a relative standard deviation of 2.5%, calculated from the peak heights obtained. The calibration graph obtained by using the preconcentration system for lead was linear with a correlation coefficient of 0.9995 for levels near the detection limit up to ? 1000 ?g/L. The method was successfully applied to the determination of lead in wine samples.