Article

RP-HPLC, with Fluorescence Detection, Assay for the Determination of Total Antioxidant Potential (TAP)

Journal of Liquid Chromatography &amp Related Technologies (Impact Factor: 0.57). 01/2012; 35:1194-1201. DOI: 10.1080/10826076.2011.619029

ABSTRACT Total Antioxidant Potential (TAP) measures the antioxidant properties of pure compounds as well as complex samples, such as food products. TAP is proportional to the product of concentrations of all antioxidants in the sample and their antioxidant powers (rate constants). TAP usually gives more information than analysis of individual antioxidants in the sample separately. In literature, hydroxyl radicals are analyzed indirectly as products of their reactions with p-hydroxybenzoic (pHBA) or terephthalic (TPA) acids. The 3,4-dihydroxybenzoic or hydroxyterephthalic acids are separated in the reversed phase HPLC and monitored using electrochemical or fluorescence detection, respectively. In our previous papers, we found that these methods can also be applied to the estimation of TAP. In this paper a TAP assay based on the hydroxyl radicals reaction with pHBA, RP-HPLC separation, and fluorometric (not electrochemical) detection is described. The assay will be compared with the previously investigated method, based on the reaction with TPA. The elaborated assay was used to evaluate TAP values of some alcoholic beverages.

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