Electrochemical Determination of the Antioxidant Capacity: The Ceric Reducing/Antioxidant Capacity (CRAC) Assay

Abstract

The CRAC assay is a direct electron transfer test of antioxidant capacity for several organic compounds. The ability of eight different compounds in reducing Ce 4þ was studied by chronoamperometric measurements of the remaining Ce 3þ species. The following antioxidant classification was observed: tannic acid ) quercetin > rutin > gallic acid % catechin > ascorbic acid > BHA > Trolox. These results agree with others already published and a good correlation (R 2 ¼ 0.937) was found with the classical spectrophotometric FRAP assay. The CRAC assay is simple, fast, free from sample pretreatment and applicable to nontransparent samples.

Antioxidant Capacity Determination in Plants and Plant‐Derived Products: A Review

“…The following trend of variation of antioxidant capacities resulted from this comparative investigation, which relied on chronoamperometric measurements: tannic acid > quercetin > rutin > gallic acid ≈ catechin > ascorbic acid > butylated hydroxyanisole > Trolox. The results were consistent with those furnished by the applied conventional FRAP assay [236]. …”

Electrochemical Methods for Total Antioxidant Capacity and its Main Contributors Determination: A review

“…This comparative study led to the following trend of variation of antioxidant capacities: tannic acid > quercetin > rutin > gallic acid ≈ catechin > ascorbic acid > butylated hydroxyanisole > Trolox. The results are in agreement with those provided by previous studies, and the consistency with the classical FRAP assay was confirmed as well [118].…”

“…The Ceric Reducing Antioxidant Capacity (CRAC) assay was also investigated with respect to the direct electron transfer facility, for determining the antioxidant capacity of eight organic compounds, relying on their ability to reduce the oxidized form of the redox couple [118]. The proposed methodology consisted in following the reduction of the Ce 4+ concentration after its interaction, during 4 min, with the sample antioxidants.…”

Biamperometric Applications to Antioxidant Content and Total Antioxidant Capacity Assessment: An Editorial

“…The following trend of variation of antioxidant capacities resulted from this comparative investigation that relied on chronoamperometric measurements: tannic acid > quercetin > rutin > gallic acid ≈ catechin > ascorbic acid > butylated hydroxyanisole > Trolox. The results were consistent with those furnished by previous studies, and by the applied conventional FRAP assay [18].…”

“…The ceric reducing antioxidant capacity assay was also exploited by virtue of its direct electron transfer facility, for determining the antioxidant capacity of eight antioxidant compounds, also based on the capacity to reduce the oxidized form of the redox couple [18]. The developed technique was based on observing the decrease of the Ce 4+ concentration after its reaction with tested antioxidants.…”