Analytical innovations in the detection of phenolics in wines.
A liquid chromatographic method with online photometric and luminescent detection for the determination of 18 phenolic compounds in wines is reported. Photometric detection is performed at four wavelengths, namely, 256, 280, 320, and 365 nm, using a diode array detection system. The luminescent detection is achieved by means of a postcolumn derivatization reaction of 10 of these compounds with terbium(III) in the presence of synergistic agents, such as ethylenediaminetetraacetic acid (EDTA) and n-octyltriphosphine oxide (TOPO). A micellar medium provided by the surfactants sodium dodecyl sulfate and Triton X-100 was used for the determination of the luminescent chelates at lambdaex 317 and lambdaem 545 nm. The long wavelength emission of lanthanide chelates can minimize interferences from background sample matrix, which usually emit at shorter wavelengths. The analytical features of the photometric and fluorometric methods, such as dynamic ranges of the calibration graphs, detection limits, and precision data, have been obtained. The practical usefulness of the developed methods is demonstrated by the analysis of Spanish and Italian wine samples (red, rosé, oloroso, and white), which were diluted and directly injected into the chromatographic system. The accuracy of both methods was checked by assaying a recovery study, which was performed at three different analyte levels for each type of sample.
Russo
Pietro
P
Department of Analytical Chemistry, Marie Curie Annex building, Campus of Rabanales, University of Córdoba, Córdoba, Spain.
Andreu-Navarro
Alvaro
A
Aguilar-Caballos
María-Paz
MP
Fernández-Romero
Juan-Manuel
JM
Gómez-Hens
Agustina
A
D002614:Chelating Agents; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D004492:Edetic Acid; D007202:Indicators and Reagents; D009943:Organophosphorus Compounds; D010636:Phenols / Q000032:analysis*; D013501:Surface-Active Agents; D014920:Wine / Q000032:analysis*
D002614:Chelating Agents; D007202:Indicators and Reagents; D009943:Organophosphorus Compounds; D010636:Phenols; D013501:Surface-Active Agents; C044965:trioctyl phosphine oxide; D004492:Edetic Acid