A new colorimetric DPPH• scavenging activity method with no need for a spectrophotometer applied on synthetic and natural antioxidants and medicinal herbs

Abstract

2,2-Diphenyl-1-picrylhydrazyl (DPPH ) radical scavenging, the most commonly used antioxidant methodwith more than seventeen thousand articles cited, is very practical; however, as with most assays, it hasthe major disadvantage of dependence on a spectrophotometer. To overcome this drawback, the colori-metric determination of the antioxidant activity using a scanner and freely available Image J software wasdeveloped. In this new method, the mixtures of solutions of DPPH and standard antioxidants or extractsof common medicinal herbs were dropped onto TLC plates, after an incubation period. The spot imageswere evaluated with Image J software to determine CSC50values, the sample concentrations providing50% colour reduction, which were very similar with the SC50values obtained with spectrophotometricmethod. The advantages of the new method are the use of lower amounts of reagents and solvents, noneed for costly spectrophotometers, and thus significantly lowered costs, and convenient implementationin any environment and situation