Sol-Gel Mediated Greener Synthesis of γ-Fe₂O₃ Nanostructures for the Selective and Sensitive Determination of Uric Acid and Dopamine

Abstract

Novel eco-freindly benign morphology-controlled biosynthesis of acicular iron oxide (γ-Fe2O3) nanostructures with various shapes and sizes have been synthesized through greener surfactant, Aloe vera (AV) extract assisted sol-gel method. By simply varying the experimental parameters, pure phase of cubic spinel superparamagnetic γ-Fe2O3 nanospherical aggregates, nanobelts and nanodots have been developed. The synthesized γ-Fe2O3 nanostructures are characterized through X-Ray Diffractommetry (XRD), X-Ray Photoelectron Spectroscopy (XPS), Fourier Transform-Infrared Spectrsocopy (FT-IR), Field Emission-Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometer (VSM). Moreover, the electrochemical determination of uric acid (UA) and dopamine (DA) of the as obtained γ-Fe2O3 nanostructures are systematically demonstrated. The electrochemical properties of the γ-Fe2O3 nanostructures modified glassy carbon electrode (GCE) displayed an excellent sensing capability for the determination of DA and UA, simultaneously than the bare GCE. When compared with the other iron oxide nanostructures, γ-Fe2O3 nanobelts/GCE exhibited remarkable oxidation current response towards the biomolecules. This occurred due to the high surface area and the unique one-dimensional nanostructure of γ-Fe2O3 nanobelts. Ultimately, the greener synthesis protocol explored in this research work may also be expanded for the preparation of other morphology controlled magnetic and non-magnetic nanomaterials, which could easily open up innovative potential avenues for the development of practical biosensors.

Keywords

• sol-gel
• greener surfactant
• iron oxide
• nanobelts
• superparamagnetism
• biosensors