Microwave assisted solvothermal green synthesis of Fe₃O₄ nanoparticles using sea buckthorn for multiple myeloma and monocytic leukemia treatment

This study presents a microwave-solvothermal green synthesis of magnetite (Fe₃O₄) nanoparticles (NPs) using Hippophae rhamnoides berry extract and evaluates their selective anticancer activity. The NPs exhibited a crystalline structure (XRD peaks matching JCPDS Card No. 88–0315), superparamagnetic properties (VSM: saturation magnetization 40.32 emu/g), with a primary particle size of 15.6 nm (TEM) and a hydrodynamic diameter of 93.25 nm (DLS). FTIR confirmed surface functionalization, with Fe-O bands and organic groups indicating phytochemical adsorption. In vitro assays (MTT, BrdU, Annexin V-PI) on U266 (multiple myeloma), THP-1 (acute monocytic leukemia), and L-929 (normal fibroblast) cells showed dose- and time-dependent cytotoxicity, with U266 and THP-1 viability reduced to 15.3% and 14.2% at 150 µg/mL after 48 h, respectively, while L-929 viability remained at 86.9%. Flow cytometry revealed late apoptosis as the primary cell death mechanism (86.6% in U266, 66.5% in THP-1 at 150 µg/mL), driven by caspase-3 activation and oxidative stress (elevated TOS and MDA levels). These findings demonstrate the potential of these NPs as selective anticancer agents for hematological malignancies, supported by their physicochemical and biological properties.