Synthesis and Characterization of Hematite nanostructures with high antioxidant and peroxidase mimic catalytic activity

Abstract

Herein, a facile synthesis of hematite (α-Fe2O3) nanostructures (Hm NS) by using the ultrasonication method is being reported. Typical procedure involved first of all synthesis of bulk hematite (α-Fe2O3) by the thermal transformation of ferric oxyhydroxide (FeO (OH)), which was the subsequently used as precursor to prepare ultra-small hematite nanostructures (Hm NS). The as-prepared nanomaterials were characterised by powdered X-ray diffraction analysis (p-XRD), fourier transform infrared spectroscopy (FTIR), high resolution transmission electron microscopy (TEM), and UV-Vis spectroscopy. The p-XRD and FTIR analyses confirmed the purity of as-synthesized α-Fe2O3 nanostructures. The TEM studies showed that hematite (α-Fe2O3) NS were spherical in shape, and their average size was in the range of 50 nm. Antimicrobial activity against Enterobacter aerogenes, Micrococcus luteus, Salmonella setubal, and Staphylococcus aureus was investigated. Samples were also explored for peroxidase mimic catalytic activity, indicating a value of 0.8 mM/min/mg for bulk and 0.5 mM/min/mg for HmNS. Both the samples were also investigated for enzyme inhibition, where the order of inhibition was lipase > urease > -amylase. Finally, the samples were also tested for antioxidant activity using TAC, TRP, and DPPH assays, where they represented a very high potential as a scavenger.