Redox reactions between ABTS•+ and dihydroxybenzenes as studied by cyclic voltammetry.

Redox reactions between several types of polyphenols and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+) used in a trolox equivalent antioxidant capacity (TEAC) assay were monitored by continuous cyclic voltammetry. The TEAC assay is one of the effective methods for clarifying the radical scavenging reaction mechanism of antioxidants. We obtained information on whether the reaction was a simple electron transfer, an electron transfer involving a subsequent chemical reaction of the antioxidant itself, or an electron transfer involving a coupling reaction between ABTS•+ and the antioxidant.