Preparation of reduced graphene oxide from the leaves of <i>Moringa oleifera</i> through two-stage pyrolysis and evaluation of its antibacterial and anticancer properties

Abstract The study demonstrates a green method of reduced graphene oxide (rGO) synthesis using dry leaves of the medicinal plant Moringa oleifera via two-stage pyrolysis, with and without ferrocene catalyst. The goal is to develop sustainable, biomass-derived rGOs and evaluate their antibacterial and anticancer properties. The characterization of the rGOs were done by using UV–Vis, FTIR, Raman spectrometry, XRD, thermogravimetric analysis, derivative thermogravimetric, differential thermal analysis, SEM, TEM and BET. The studies revealed the presence of multiple functional groups (C–N, O=C–O, C=O, C≡C, C–H) with crystalline sizes ranging from 42–61 nm (with catalyst) and 18–40 nm (without catalyst). Both rGOs displayed high thermal stability (residual mass 55%–65% at 917 °C) and characteristic wrinkled sheet structures. They exhibited antibacterial activity against Staphylococcus aureus and Enterococcus faecalis . Notably, the rGO prepared without a catalyst (MOL–rGO–WiOC) showed potent anticancer activity with an IC 50 value of 6.98 μ g ml −1 against MCF-7 breast cancer cells, surpassing the efficacy of the standard anticancer drug doxorubicin (IC 50 69.02 μ g ml −1 ). These findings highlight the clinical promise of biomass-derived rGO as an eco-friendly nanomaterial with antibacterial and anticancer applications.