Plant-Mediated Fabrication of Iron and Zinc Oxide Nanoparticles for Anticancer Efficacy Against HT-29 and HepG2 Cells

Objectives This study aims to valorize Fagonia arabica (Dhamasa booti) herbal waste by synthesizing bioactive iron oxide (FeO) and zinc oxide (ZnO) nanoparticles for anticancer applications. Methods Aqueous extracts of F. arabica were utilized to green-synthesize FeO and ZnO NPs. The nanoparticles were characterized for morphology, size, crystallinity and zeta potential. Their antioxidant activity, brine shrimp lethality, and hemolytic assays were performed to determine bioactivity and cyto-compatibility. Results FeO and ZnO NPs were spherical, monodispersed and polycrystalline with particle sizes of 28.8 nm and 30.4 nm, respectively. ZnO NPs showed stronger antioxidant activity (80.81% scavenging at 150 μg/mL) and higher cytotoxicity in the brine shrimp assay (LC 50 = 0.98 μg/mL), compared to FeO NPs and the crude extract. Minimal hemolytic activity, confirmed their favorable biocompatibility. Zeta potential values of -36 mV (FeO) and +33.6 mV (ZnO) indicate moderate colloidal stability. In vitro anticancer analysis revealed superior performance of ZnO NPs with IC 50 values of 43.79 µg/mL (HepG2) and 66.71 µg/mL (HT-29). Conclusion Fagonia Arabica- derived ZnO NPs exhibit potent antioxidant, cytotoxic and anticancer activities, along with favorable biocompatibility. Their significant therapeutic performance highlights their role as effective plant-mediated antineoplastic agents and supports the value-added utilization of F . arabica herbal waste.