Producing Radical‐Free Hyperpolarized Perfusion Agents for In Vivo Magnetic Resonance Using Spin‐Labeled Thermoresponsive Hydrogel. Issue 13 (17th May 2016)

• Record Type: Journal Article
• Authors: Cheng, Tian; Mishkovsky, Mor; Junk, Matthias J. N.; Münnemann, Kerstin; Comment, Arnaud
• Is Part Of: Macromolecular rapid communications. Volume 37:Issue 13(2016)
• Page Start: 1074
• Page End: 1078
• Publication Date: 2016-05-17
• Subjects: carbon‐13 MRS -- dynamic nuclear polarization -- radical‐free -- spin‐labeled thermoresponsive hydrogels; Macromolecules -- Periodicals; Polymers -- Periodicals; Chemistry -- Periodicals; 547.705
• DOI: 10.1002/marc.201600133
• Languages: English
• ISSNs: 1022-1336

Abstract

Abstract : Dissolution dynamic nuclear polarization (DNP) provides a way to tremendously improve the sensitivity of nuclear magnetic resonance experiments. Once the spins are hyperpolarized by dissolution DNP, the radicals used as polarizing agents become undesirable since their presence is an additional source of nuclear spin relaxation and their toxicity might be an issue. This study demonstrates the feasibility of preparing a hyperpolarized [1‐ 13 C]2‐methylpropan‐2‐ol ( tert ‐butanol) solution free of persistent radicals by using spin‐labeled thermoresponsive hydrophilic polymer networks as polarizing agents. The hyperpolarized 13 C signal can be detected for up to 5 min before the spins fully relax to their thermal equilibrium. This approach extends the applicability of spin‐labeled thermoresponsive hydrogel to the dissolution DNP field and highlights its potential as polarizing agent for preparing neat slowly relaxing contrast agents. The hydrogels are especially suited to hyperpolarize deuterated alcohols which can be used for in vivo perfusion imaging. Abstract : A spin‐labeled thermoresponsive hydrogel is a promising polarizing agent for preparing hyperpolarized 13 C‐labeled perfusion contrast agent such as alcohol . Its thermoresponsive characteristics allows for a quick collapse of the hydrogel after the dissolution procedure so that hyperpolarized alcohol solution, [1‐ 13 C] 2‐metylpropan‐2‐ol ( tert ‐butanol) in this case, is free of persistent radicals.