Determination Of Antioxidant Potential Using An Oxygen Radical Absorbance Capacity (ORAC) Assay With Synergy™ H4

By Peter J. Brescia, Applications Scientist, BioTek Instruments, Inc.

The oxygen radical absorbance capacity (ORAC) assay has emerged as a robust analytical method to determine the antioxidant potential of a range of substances found in neutraceutical, pharmaceutical and food products. ORAC relies on a common fluorescent probe, fluorescein, to monitor antioxidant activity which can be read on a microplate reader capable of detecting fluorescence. Here we show the ability to perform the assay in a 96-well microplate format amenable to higher throughput platforms. Intra-assay precision and accuracy were determined as well as quantification of the antioxidant capacity of several known compounds.