Kinetic study of DPPH scavenging in the presence of mixture of Zinc and Vitamin C as an antioxidant


1 Department of Chemistry, Islamic Azad University, Mashhad Branch, Mashhad, Iran

2 Department of Chemistry, Islamic Azad University, Mashhad Branch, Mashhad, Iran, young researcher club


Reactions of free radicals and reactive oxygen species (ROS) with biological molecules in vivo play an important physiological role in many diseases. 2,2-diphenyl-1-picrylhydrazyl (DPPH) is a stable free radical and often used as a routine reagent to evaluate the antioxidant capacity of an antioxidant. This study was undertaken to investigate the free radical-scavenging and antioxidant activities of Zinc, Vitamin C and mixture of them. UV-Vis spectrophotometry method was used to evaluate the ability of Zinc, Vitamin C and mixture of them to scavenge DPPH radical. The kinetic parameters such as rate constant and activation energy in experimental conditions were calculated. The rate constants of the H atom abstraction by DPPH (), in the presence of Zinc, Vitamin C and mixture of them were obtained (0.4209, 2.092 and 1.82 min-1) respectively, under pseudo-first-order conditions at 25 oC.


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