TY - JOUR

T1 - Constant-adiabaticity ultralow magnetic field manipulations of parahydrogen-induced polarization

T2 - application to an AA'X spin system

AU - Rodin, Bogdan A.

AU - Eills, James

AU - Picazo-Frutos, Román

AU - Sheberstov, Kirill F.

AU - Budker, Dmitry

AU - Ivanov, Konstantin L.

N1 - Publisher Copyright: © the Owner Societies 2021.

PY - 2021/3/28

Y1 - 2021/3/28

N2 - The field of magnetic resonance imaging with hyperpolarized contrast agents is rapidly expanding, and parahydrogen-induced polarization (PHIP) is emerging as an inexpensive and easy-to-implement method for generating the required hyperpolarized biomolecules. Hydrogenative PHIP delivers hyperpolarized proton spin order to a substrateviachemical addition of H2in the spin-singlet state, but it is typically necessary to transfer the proton polarization to a heteronucleus (usually13C) which has a longer spin lifetime. Adiabatic ultralow magnetic field manipulations can be used to induce the polarization transfer, but this is necessarily a slow process, which is undesirable since the spins continually relax back to thermal equilibrium. Here we demonstrate two constant-adiabaticity field sweep methods, one in which the field passes through zero, and one in which the field is swept from zero, for optimal polarization transfer on a model AA′X spin system, [1-13C]fumarate. We introduce a method for calculating the constant-adiabaticity magnetic field sweeps, and demonstrate that they enable approximately one order of magnitude faster spin-order conversion compared to linear sweeps. The present method can thus be utilized to manipulate nonthermal order in heteronuclear spin systems.

AB - The field of magnetic resonance imaging with hyperpolarized contrast agents is rapidly expanding, and parahydrogen-induced polarization (PHIP) is emerging as an inexpensive and easy-to-implement method for generating the required hyperpolarized biomolecules. Hydrogenative PHIP delivers hyperpolarized proton spin order to a substrateviachemical addition of H2in the spin-singlet state, but it is typically necessary to transfer the proton polarization to a heteronucleus (usually13C) which has a longer spin lifetime. Adiabatic ultralow magnetic field manipulations can be used to induce the polarization transfer, but this is necessarily a slow process, which is undesirable since the spins continually relax back to thermal equilibrium. Here we demonstrate two constant-adiabaticity field sweep methods, one in which the field passes through zero, and one in which the field is swept from zero, for optimal polarization transfer on a model AA′X spin system, [1-13C]fumarate. We introduce a method for calculating the constant-adiabaticity magnetic field sweeps, and demonstrate that they enable approximately one order of magnitude faster spin-order conversion compared to linear sweeps. The present method can thus be utilized to manipulate nonthermal order in heteronuclear spin systems.

UR - http://www.scopus.com/inward/record.url?scp=85103685764&partnerID=8YFLogxK

U2 - 10.1039/d0cp06581a

DO - 10.1039/d0cp06581a

M3 - Article

C2 - 33876078

AN - SCOPUS:85103685764

VL - 23

SP - 7125

EP - 7134

JO - Physical Chemistry Chemical Physics

JF - Physical Chemistry Chemical Physics

SN - 1463-9076

IS - 12

ER -