by Keyword: Radicals

Barskiy, DA, Blanchard, JW, Budker, D, Stern, Q, Eills, J, Elliott, SJ, Picazo-Frutos, R, Garcon, A, Jannin, S, Koptyug, IV, (2023). Possible Applications of Dissolution Dynamic Nuclear Polarization in Conjunction with Zero- to Ultralow-Field Nuclear Magnetic Resonance Applied Magnetic Resonance 54, 1221-1240

The combination of a powerful and broadly applicable nuclear hyperpolarization technique with emerging (near-)zero-field modalities offers novel opportunities in a broad range of nuclear magnetic resonance spectroscopy and imaging applications, including biomedical diagnostics, monitoring catalytic reactions within metal reactors and many others. These are discussed along with a roadmap for future developments.

JTD Keywords: Couplings, Hyperpolarization, Nmr, Parahydrogen, Phase, Radicals, Time

Blasi, D, Gonzalez-Pato, N, Rodriguez, XR, Diez-Zabala, I, Srinivasan, SY, Camarero, N, Esquivias, O, Roldán, M, Guasch, J, Laromaine, A, Gorostiza, P, Veciana, J, Ratera, I, (2023). Ratiometric Nanothermometer Based on a Radical Excimer for In Vivo Sensing Small 19, 2207806

Ratiometric fluorescent nanothermometers with near-infrared emission play an important role in in vivo sensing since they can be used as intracellular thermal sensing probes with high spatial resolution and high sensitivity, to investigate cellular functions of interest in diagnosis and therapy, where current approaches are not effective. Herein, the temperature-dependent fluorescence of organic nanoparticles is designed, synthesized, and studied based on the dual emission, generated by monomer and excimer species, of the tris(2,4,6-trichlorophenyl)methyl radical (TTM) doping organic nanoparticles (TTMd-ONPs), made of optically neutral tris(2,4,6-trichlorophenyl)methane (TTM-αH), acting as a matrix. The excimer emission intensity of TTMd-ONPs decreases with increasing temperatures whereas the monomer emission is almost independent and can be used as an internal reference. TTMd-ONPs show a great temperature sensitivity (3.4% K-1 at 328 K) and a wide temperature response at ambient conditions with excellent reversibility and high colloidal stability. In addition, TTMd-ONPs are not cytotoxic and their ratiometric outputs are unaffected by changes in the environment. Individual TTMd-ONPs are able to sense temperature changes at the nano-microscale. In vivo thermometry experiments in Caenorhabditis elegans (C. elegans) worms show that TTMd-ONPs can locally monitor internal body temperature changes with spatio-temporal resolution and high sensitivity, offering multiple applications in the biological nanothermometry field.© 2023 The Authors. Small published by Wiley-VCH GmbH.

JTD Keywords: dual emission, elegans, excimer emission, fluorescence, in vivo sensing, luminescence, nanoparticles, organic radical nanoparticles, ratiometric nanothermometers, sensors, thermometry, trityl radicals, Caenorhabditis elegans, Excimer emission, In vivo sensing, Intracellular ph, Luminescence, Organic radical nanoparticles, Ratiometric nanothermometers, Trityl radicals

Simao, C., Mas-Torrent, M., Crivillers, N., Lloveras, V., Artés, Juan Manuel, Gorostiza, Pau, Veciana, Jaume, Rovira, C., (2011). A robust molecular platform for non-volatile memory devices with optical and magnetic responses Nature Chemistry , 3, (5), 359-364

Bistable molecules that behave as switches in solution have long been known. Systems that can be reversibly converted between two stable states that differ in their physical properties are particularly attractive in the development of memory devices when immobilized in substrates. Here, we report a highly robust surface-confined switch based on an electroactive, persistent organic radical immobilized on indium tin oxide substrates that can be electrochemically and reversibly converted to the anion form. This molecular bistable system behaves as an extremely robust redox switch in which an electrical input is transduced into optical as well as magnetic outputs under ambient conditions. The fact that this molecular surface switch, operating at very low voltages, can be patterned and addressed locally, and also has exceptionally high long-term stability and excellent reversibility and reproducibility, makes it a very promising platform for non-volatile memory devices.

JTD Keywords: Self-assembled monolayers, Chromophore-based monolayers, Ultrathin platinum films, Carbon free-radicals, Per-million levels, Polychlorotriphenylmethyl radicals, Electron-transfer, Surface, Logic, Quantification