Light-Driven Dissolution of Ultrasmall Maghemite Nanoparticles: The Role of Ligand and Photon Energy
Year: 2026
Type: preprint
Abstract: Light-controlled conversion of iron oxide nanoparticles into redox-active soluble iron offers a route toward externally triggered, image-guided ferroptosis strategies, but the physicochemical factors governing this process remain poorly understood. Here, visible-light-driven dissolution of ultrasmall citrate-stabilized maghemite nanoparticles (3.4 ± 0.8 nm) is shown to arise from a competition between iron release and nanoparticle aggregation. The process involves iron oxide reduction, ferrous iron release, citrate detachment and oxidation, and subsequent nanoparticle aggregation. The effects of citric acid and photon energy are systematically examined, revealing their key roles in regulating dissolution and aggregation. Magnetic resonance imaging (MRI) and spatially resolved diffuse reflectance are used to monitor these changes in biologically relevant environments, including tissue-mimicking phantoms. MRI contrast evolves predictably with irradiation time, supporting the use of these particles as responsive imaging probes. In glioblastoma cells, green-light irradiation of internalized maghemite nanoparticles induces mitochondrial cytochrome oxidation. Cell-viability assays further reveal a non-monotonic concentration dependence under blue and green light, with lower nanoparticle concentrations producing stronger cytotoxic effects. These results establish a light-controlled, ligandassisted dissolution/aggregation strategy in which photon energy and ligand availability govern iron release, colloidal stability, imaging response, and light-induced cellular toxicity.
Source: ChemRxiv
Authors: Dmitrii Tsiurko, Ekaterina Moiseeva, Sergei German, Daria Terentyeva, Arsen Zotov, Alina Platonova, Vsevolod Skribitsky, Nadezda Brazhe, Zhanna Bochkova, Alexander Vaneev, Semen Domarev, Timofei Torokhov, Sergey Kulikov, Victoria Turubanova, Alexander Erofeev, Vladimir Oleinikov, Alexey Lipengolts, Anna Orlova, Dmitry Gorin
Institutions: Skolkovo Institute of Science and Technology, Prokhorov General Physics Institute, Russian Cancer Research Center NN Blokhin, Lomonosov Moscow State University, Institute of Bioorganic Chemistry, National University of Science and Technology, ITMO University, Sirius University of Science and Technology, N. I. Lobachevsky State University of Nizhny Novgorod
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7220678648