In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 100, No. 18 ( 2003-09-02), p. 10158-10163
Abstract:
A method for obtaining strongly polarized nuclear spins in solution has
been developed. The method uses low temperature, high magnetic field, and dynamic nuclear polarization (DNP) to strongly polarize nuclear spins in the
solid state. The solid sample is subsequently dissolved rapidly in a suitable solvent to create a solution of molecules with hyperpolarized nuclear spins.
The polarization is performed in a DNP polarizer, consisting of a super-conducting magnet (3.35 T) and a liquid-helium cooled sample space. The
sample is irradiated with microwaves at ≈94 GHz. Subsequent to polarization, the sample is dissolved by an injection system inside the DNP
magnet. The dissolution process effectively preserves the nuclear polarization. The resulting hyperpolarized liquid sample can be transferred to
a high-resolution NMR spectrometer, where an enhanced NMR signal can be acquired, or it may be used as an agent for in vivo imaging or
spectroscopy. In this article we describe the use of the method on aqueous solutions of [ 13 C]urea. Polarizations of 37% for 13 C and
7.8% for 15 N, respectively, were obtained after the dissolution.
These polarizations correspond to an enhancement of 44,400 for 13 C
and 23,500 for 15 N, respectively, compared with thermal equilibrium
at 9.4 T and room temperature. The method can be used generally for signal enhancement and reduction of measurement time in liquid-state NMR and opens up
for a variety of in vitro and in vivo applications of
DNP-enhanced NMR.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.1733835100
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
2003
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12
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