Development of bioengineered SPIONs using Carica monoica extract: evaluation of antioxidant and anticancer activity of human cervical cancer cells (SiHa)

Abstract This study pioneers the green synthesis of SPIONs using a novel bioresource: Carica monoica leaf extract as a reducing and capping agent. This method not only emphasizes sustainability but also uniquely leverages the specific phytochemical profile of C. monoica to create a synergistic therapeutic platform. Comprehensive characterization using UV-vis, XRD, TEM, EDX, and FTIR, Zeta potential and VSM confirmed the successful creation of hexagonal, superparamagnetic nanoparticles with an average size of 30–50 nm. The biological activity of these CM-SPIONs revealed a dual and potent functionality. Multiple assays showed the nanoparticles have significantly enhanced, dose-dependent antioxidant activity, indicating a nano-bio synergy that amplifies the phytoconstituents’ effects. More importantly, this antioxidant potential translated into selective and potent anticancer efficacy against human cervical cancer (SiHa) cells. MTT assay revealed potent, dose-dependent cytotoxicity with a notably low IC 50 value of 22 ± 0.7 μg/ml. Fluorescence microscopy using AO/EtBr and DAPI staining confirmed that the mechanism of cell death was predominantly apoptosis, providing initial mechanistic insight. Thus, CM-SPIONs function as an active nanotherapeutic agent, demonstrating the potential of novel plant biosystems to yield sustainable nanomedicines with dual antioxidant and pro-apoptotic efficacy.