title: Usefulness of palladium impregnated magnetite nanoparticles for polyphenol determination.
abstract: Palladium impregnated magnetite nanoparticles (Pd-Fe3O4NPs) have been synthesized and used as reusable catalyst for the fluorometric determination of polyphenols in wines. The method is based on the decrease of the indocyanine green fluorescence, which is ascribed to its oxidation by dissolved oxygen in the presence of the nanoparticles, and the inhibition of the fluorescence decrease by polyphenols, which is proportional to the polyphenol concentration. The dynamic range of the calibration graph is 0.1-10.0µM gallic acid, which was chosen as model analyte, and the detection limit is 0.02µM. Precision data, expressed as relative standard deviation, ranged between 3.3% and 5.4%. The method was applied to the analysis of several wine samples, obtaining recovery values in the range of 79.7-102.0%. The results obtained were compared with those obtained using the Folin-Ciocalteu and laccase methods, finding that Pd-Fe3O4NPs provide a better selectivity than the first method and show a catalytic behavior similar to that of laccase.
authors.affiliation: Analytical Chemistry Department, Institute of Fine Chemistry and Nanochemistry, Campus of Rabanales, Annex to Marie Curie Building, University of Córdoba, 14071 Córdoba, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Godoy-Navajas
authors.affiliation: Analytical Chemistry Department, Institute of Fine Chemistry and Nanochemistry, Campus of Rabanales, Annex to Marie Curie Building, University of Córdoba, 14071 Córdoba, Spain.
authors.forename: María Paz
authors.initials: MP
authors.lastname: Aguilar-Caballos
authors.affiliation: Analytical Chemistry Department, Institute of Fine Chemistry and Nanochemistry, Campus of Rabanales, Annex to Marie Curie Building, University of Córdoba, 14071 Córdoba, Spain. Electronic address: qa1gohea@uco.es.
authors.forename: Agustina
authors.initials: A
authors.lastname: Gómez-Hens
mesh_terms: D042845:Laccase; D058185:Magnetite Nanoparticles; D010165:Palladium; D059808:Polyphenols; D014920:Wine
chemical_list: D058185:Magnetite Nanoparticles; D059808:Polyphenols; D010165:Palladium; D042845:Laccase
keywords: Fluorometric detection; Indocyanine green; Magnetic palladium nanoparticles; Polyphenols; Wine analysis