Antioxidant capacity of edaravone, quercetin, and myricetin involving probabilistic fluctuations using eosin-Y and eosin-B as fluorescent probes in the ORAC assay

The oxygen radical absorbance capacity (ORAC) assay measures the antioxidant activity of the antioxidants through competitive consumption of peroxyl radicals relative to a fluorescent probe. This study evaluated fluorescein (FLH), eosin Y, and eosin B in ORAC assays using quantum computations. In ORAC-FLH assays, trolox (TRO) and ascorbic acid (ASC) showed fluorescence decay kinetics with a lag time, blocking initial reactions in the quenching cascade. Eosins were more reactive towards peroxyl radicals, making TRO assessment infeasible in ORAC-eosin assays. Quercetin and myricetin exhibited sigmoidal curve drifts proportional to squared and 3/2-ordered incubation times, indicating probabilistic fluorescence decay. Edaravone (EDA) weakly inhibited initial reactions, with accelerated quenching over time. In ORAC-eosin assays, flavonoids and EDA showed indistinguishable behavior due to high eosin reactivity. ORAC-FLH did not significantly assess BHT, though a dose-dependent change in half-life was noted. This study suggests broad applications for ORAC-eosin assays and potential for future comparative research.