Innovative Agrowaste Banana Peel Extract-Based Magnetic Iron Oxide Nanoparticles for Eco-Friendly Oxidative Shield and Freshness Fortification

Abstract

Abstract This study presents the synthesis of agrowaste banana peel extract-based magnetic iron oxide nanoparticles (BPEx-MIONPs), emphasizing antioxidant capacity and food preservation. Using iron (III) chloride hexahydrate (FeCl3 · 6 H2O) as a precursor and a reducing agent from agrowaste peel extract, a precisely controlled process yielded BPEx-MIONPs. Characterization involved X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). XRD revealed tetragonal Fe2O3, cubic magnetite structure, and monoclinic FexOy-NPs with an average size of 14.8 nm. TEM and SEM showcased diverse morphologies—cubic, quasi-spherical, and elongated microdomains. FTIR confirmed Fe–O bonds (1000 − 400 cm-1). Antioxidant assessment showed robust DPPH free radical scavenging; BPEx achieved 100% inhibition at 18 min, and BPEx-MIONPs had an IC50 of ~ 136 µg/mL. BPEx-MIONPs, stabilized with banana-based bioplastic, effectively preserved grapes, reducing weight loss to 6.2% on day 3, compared to the control (19.0%). This pioneering study combines banana peel antioxidants with magnetic iron oxide nanoparticles, providing sustainable solutions for food preservation and nano-packaging. Ongoing research aims to refine conditions and explore broader applications of BPEx-MIONPs.