title: Generalizing, Extending, and Maximizing Nitrogen-15 Hyperpolarization Induced by Parahydrogen in Reversible Exchange.
abstract: Signal Amplification by Reversible Exchange (SABRE) is a fast and convenient NMR hyperpolarization method that uses cheap and readily availablepara-hydrogen as a hyperpolarization source. SABRE can hyperpolarize protons and heteronuclei. Here we focus on the heteronuclear variant introduced as SABRE-SHEATH (SABRE in SHield Enables Alignment Transfer to Heteronuclei) and nitrogen-15 targets in particular. We show that15N-SABRE works more efficiently and on a wider range of substrates than1H-SABRE, greatly generalizing the SABRE approach. In addition, we show that nitrogen-15 offers significantly extendedT1times of up to 12 minutes. LongT1times enable higher hyperpolarization levels but also hold the promise of hyperpolarized molecular imaging for several tens of minutes. Detailed characterization and optimization are presented, leading to nitrogen-15 polarization levels in excess of 10% on several compounds.
authors.affiliation: Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
authors.forename: Johannes F P
authors.initials: JF
authors.lastname: Colell
authors.affiliation: Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
authors.forename: Angus W J
authors.initials: AW
authors.lastname: Logan
authors.affiliation: Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
authors.forename: Zijian
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Vanderbilt University Institute of Imaging Science (VUIIS), Department of Radiology, Department of Biomedical Engineering, Vanderbilt Ingram Cancer Center (VICC), Vanderbilt University , Nashville, Tennessee 37232, United States.
authors.forename: Roman V
authors.initials: RV
authors.lastname: Shchepin
authors.affiliation: Vanderbilt University Institute of Imaging Science (VUIIS), Department of Radiology, Department of Biomedical Engineering, Vanderbilt Ingram Cancer Center (VICC), Vanderbilt University , Nashville, Tennessee 37232, United States.
authors.forename: Danila A
authors.initials: DA
authors.lastname: Barskiy
authors.affiliation: Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
authors.forename: Gerardo X
authors.initials: GX
authors.lastname: Ortiz
authors.affiliation: Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
authors.forename: Qiu
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Malcolmson
authors.affiliation: Vanderbilt University Institute of Imaging Science (VUIIS), Department of Radiology, Department of Biomedical Engineering, Vanderbilt Ingram Cancer Center (VICC), Vanderbilt University, Nashville, Tennessee 37232, United States; Russian Academy of Sciences, Moscow, Russia.
authors.forename: Eduard Y
authors.initials: EY
authors.lastname: Chekmenev
authors.affiliation: Department of Chemistry, Duke University, Durham, North Carolina 27708, United States; Departments of Physics, Radiology and Biomedical Engineering, Duke University, Durham, North Carolina 27707, United States.
authors.forename: Warren S
authors.initials: WS
authors.lastname: Warren
authors.affiliation: Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
authors.forename: Thomas
authors.initials: T
authors.lastname: Theis