Novel Free-Radical Scavengers Based on Ferrofluid/Polyaniline Nanocomposites

Abstract

We investigated the antioxidant activity of novel ferrofluid/polyaniline nanocomposites with various mass ratios synthesized via in situ chemical oxidative polymerization of aniline without stirring in the presence of stabilized Fe₃O₄ nanoparticles and citric acid as a surfactant. The structural, morphological, thermal, magnetic, and electrical properties of the nanocomposites were characterized by IR and UV spectroscopy, XRD, SEM, TEM, TGA, VSM, and four-point-probe methods. The antioxidant potency was determined by modified 2,2-diphenyl-1-picrylhydrazyl (DPPH) method using an in vitro system. The DPPH free-radical scavenging tests of nanocomposites showed that their antioxidant properties depended on the amount of polyaniline in the composition. Results of the comparison of DPPH scavenging capacity of nanofiber polyaniline and granular ferrofluid/polyaniline nanocomposite show that the antioxidant activity is related to the morphology of polyaniline.