Baudouin D, van Kalkeren H A, Bornet A, Vuichoud B, Veyre L, Cavaillès M, Schwarzwälder M, Liao W-C, Gajan D, Bodenhausen G, Emsley L, Lesage A, Jannin S, Copéret C, Thieuleux C
Université de Lyon , Institut de Chimie de Lyon , LC2P2 , UMR 5265 CNRS-CPE Lyon-UCBL , CPE Lyon , 43 Bvd du 11 Novembre 1918 , 69100 Villeurbanne , France . Email:
Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland.
Chem Sci. 2016 Nov 1;7(11):6846-6850. doi: 10.1039/c6sc02055k. Epub 2016 Jul 18.
Hyperpolarization of metabolites by dissolution dynamic nuclear polarization (D-DNP) for MRI applications often requires fast and efficient removal of the radicals (polarizing agents). Ordered mesoporous SBA-15 silica materials containing homogeneously dispersed radicals, referred to as HYperPolarizing SOlids (HYPSOs), enable high polarization - (H) = 50% at 1.2 K - and straightforward separation of the polarizing HYPSO material from the hyperpolarized solution by filtration. However, the one-dimensional tubular pores of SBA-15 type materials are not ideal for nuclear spin diffusion, which may limit efficient polarization. Here, we develop a generation of hyperpolarizing solids based on a SBA-16 structure with a network of pores interconnected in three dimensions, which allows a significant increase of polarization, (H) = 63% at 1.2 K. This result illustrates how one can improve materials by combining a control of the incorporation of radicals with a better design of the porous network structures.
用于磁共振成像（MRI）应用的溶解动态核极化（D-DNP）使代谢物超极化通常需要快速有效地去除自由基（极化剂）。含有均匀分散自由基的有序介孔SBA-15硅材料，称为超极化固体（HYPSOs），能够实现高极化——在1.2 K时达到50%——并且通过过滤可直接从超极化溶液中分离出极化的HYPSO材料。然而，SBA-15型材料的一维管状孔对于核自旋扩散并不理想，这可能会限制有效极化。在此，我们基于具有三维互连孔网络的SBA-16结构开发了一代超极化固体，其在1.2 K时极化显著增加，达到63%。这一结果说明了如何通过将自由基掺入的控制与多孔网络结构更好的设计相结合来改进材料。
