Nitroxide radical contrast agents for safe magnetic resonance imaging: progress, challenges, and perspectives

Materials Horizons, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Magnetic resonance imaging (MRI) is considered one of the most valuable diagnostic technologies in 21st century. To enhance image contrast anatomical features, MRI agents have been widely used clinical diagnosis, especially those based on gadolinium, manganese, and iron oxide. However, these metal-based show potential toxicity to patients, which urges researchers develop novel that can replace agents. Metal-free nitroxide radical (NRCAs) effectively overcome shortcomings also many advantages, including good biocompatibility, prolonged systemic circulation time, easily functionalized structures. Importantly, since NRCAs acquire signals with standard tissue water

Язык: Английский

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Nanomaterials in gastric cancer: pioneering precision medicine for diagnosis, therapy, and prevention

Medical Oncology, Год журнала: 2025, Номер 42(4)

Опубликована: Март 6, 2025

Язык: Английский

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Towards Metabolic Organic Radical Contrast Agents (mORCAs) for Magnetic Resonance Imaging

Molecules, Год журнала: 2025, Номер 30(7), С. 1581 - 1581

Опубликована: Апрель 2, 2025

We report two conjugates of gem-diethyl pyrroline nitroxide radicals with D-mannosamine as potential metabolic organic radical contrast agents, mORCAs, circumventing the need for biorthogonal reactions. In-cell EPR spectroscopy, using Jurkat cells and analogous conjugate, based on a pyrrolidine radical, shows an efficient incorporation highly immobilized nitroxides, correlation time τcor = 20 ns. In vivo MRI experiments in mice show that paramagnetic shortens T1 T2 relaxation times protons water located kidney brain by only up to ~10% after 3 d. Ex spectroscopic analyses indicate agents mouse tissues are primarily localized kidney, lung, liver, heart, blood, which contain 4–9 The spin concentrations remain low (1–3 nmol g⁻1) at 24 h third mORCA injection, approximately one orders magnitude lower than those ORCAFluor BASP-ORCA (measured ~24 post-injection). These explain small proton changes observed MRI.

Язык: Английский

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Coordination clusters as emerging magnetic resonance imaging contrast agents

Опубликована: Май 1, 2025

Язык: Английский

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