Can an abts antioxidant test be performed without a spectrophotometer?

Abstract

ABTS• + (2,2-azinobis- (3-ethylbenzothiazoline-6-sulphonic acid)) radical scavenging assay is widely used to determine the antioxidant activity of natural and synthetic substances. As other antioxidant activity determination methods, a spectrophotometer device is needed to determine the numerical value of the color formed in ABTS method. Therefore, the dependence on the device is disadvantageous due to especially the high cost and restriction of workspace. To overcome this disadvantage, a new colorimetric method in the determination of antioxidant activity for ABTS method was developed with the help of a scanner device and free software (Image J). Mixtures (plant extracts and antioxidant standards) in this new colorimetric method were prepared as in the spectrophotometric method and, after the incubation period, each of these reagent mixtures was dropped onto the thin layer chromatography (TLC) plate. Then the colors that appeared on the thin layer chromatography were transferred to the computer with the help of a scanner and CSC50 values (the color value of the antioxidant concentration required to scavenge 50% of the ABTS radical in the test solution using Image J software) were measured with free software of Image J. The same measurements were performed simultaneously on the spectrophotometer. The results of both methods were compared. There was a strong correlation between the new colorimetric method and the spectrophotometric method for ABTS. Thus, the new colorimetric method for the ABTS test has become easily applicable since no spectrophotometer device is needed and in all environments.