title: On-line complexation/preconcentration system for the determination of lead in wine by inductively coupled plasma-atomic emission spectrometry with ultrasonic nebulization.
abstract: 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 pneumatic 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 microg/L. The precision for 10 replicate determinations at a Pb level of 25 microg/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 > or = 1000 microg/L. The method was successfully applied to the determination of lead in wine samples.
authors.affiliation: National University of San Luis, Faculty of Chemistry, Department of Analytical Chemistry, Argentina.
authors.forename: R G
authors.initials: RG
authors.lastname: Wuilloud
authors.forename: A H
authors.initials: AH
authors.lastname: González
authors.forename: E J
authors.initials: EJ
authors.lastname: Marchevsky
authors.forename: R A
authors.initials: RA
authors.lastname: Olsina
authors.forename: L D
authors.initials: LD
authors.lastname: Martinez
mesh_terms: D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007854:Lead / Q000032:analysis*; D009862:Online Systems; D015203:Reproducibility of Results; D013054:Spectrophotometry, Atomic; D014465:Ultrasonics; D014920:Wine / Q000032:analysis*
chemical_list: D007202:Indicators and Reagents; D007854:Lead