New room temperature coacervation scheme for lead traces determination by solid surface fluorescence. Application to wines produced in Argentina

TALÍO, MARÍA CAROLINA; KAPLAN, MARCOS; ACOSTA, MARIANO; GIL, RAÚL; LUCONI, MARTA OLGA; FERNANDEZ, LILIANA

MICROCHEMICAL JOURNAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015 vol. 123 p. 237 - 242

0026-265X

Lead traces were preconcentrated on paper filter discs using the coacervation phenomenon based on cationic andanionic surfactant reaction at room temperature. The increase in fluorescent signal of Rhodamine B dye was usedfor metal quantification by solid surface fluorescence. Experimental variables that influence on preconcentrationstep and fluorimetric sensitivity were optimized using uni-varied assays. The calibration graph using zeroth orderregression was linear from 1.24 × 10−3 μg L−1 to 1.25 μg L−1 with a correlation coefficient of 0.997. At the exper-imental optimal conditions, a limit of detection of 3.73 × 10−4 μg L−1 and a limit of quantification of1.24 × 10−3 μg L−1 were obtained. The method showed good sensitivity, adequate selectivity with good toler-ance to foreign ions, and was applied to the determination of trace amounts of Pb(II) in red and white wines pro-duced in Argentina with satisfactory results validated by ICP-MS. The proposed method represents an innovativeapplication of paper filters to solid surface fluorescence methodology.