Katz Itai, Blank Aharon
Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Haifa 32000, Israel.
Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Haifa 32000, Israel.
J Magn Reson. 2015 Dec;261:95-100. doi: 10.1016/j.jmr.2015.10.009. Epub 2015 Oct 26.
Dynamic nuclear polarization (DNP) is a method for enhancing nuclear magnetic resonance (NMR) signals that has many potential applications in chemistry and medicine. Traditionally, DNP signal enhancement is achieved through the use of exogenous radicals mixed in a solution with the molecules of interest. Here we show that proton DNP signal enhancements can be obtained for solid samples without the use of solvent and exogenous radicals. Radicals are generated primarily on the surface of a solid sample using electrical discharges. These radicals are found suitable for DNP. They are stable under moderate vacuum conditions, yet readily annihilate upon compound dissolution or air exposure. This feature makes them attractive for use in medical applications, where the current variety of radicals used for DNP faces regulatory problems. In addition, this solvent-free method may be found useful for analytical NMR of solid samples which cannot tolerate solvents, such as certain pharmaceutical products.
动态核极化（DNP）是一种增强核磁共振（NMR）信号的方法，在化学和医学领域有许多潜在应用。传统上，DNP信号增强是通过将外源性自由基与感兴趣的分子混合在溶液中来实现的。在此我们表明，无需使用溶剂和外源性自由基即可在固体样品中获得质子DNP信号增强。自由基主要通过放电在固体样品表面产生。这些自由基被发现适用于DNP。它们在适度真空条件下稳定，但在化合物溶解或暴露于空气中时容易湮灭。这一特性使其在医学应用中具有吸引力，因为目前用于DNP的各种自由基面临监管问题。此外，这种无溶剂方法可能对无法耐受溶剂的固体样品（如某些药品）的分析NMR有用。
