TY - JOUR
T1 - PASADENA hyperpolarization of succinic acid for MRI and NMR spectroscopy
AU - Chekmenev, Eduard Y.
AU - Hövener, Jan
AU - Norton, Valerie A.
AU - Harris, Kent
AU - Batchelder, Lynne S.
AU - Bhattacharya, Pratip
AU - Ross, Brian D.
AU - Weitekamp, Daniel P.
PY - 2008/4/2
Y1 - 2008/4/2
N2 - We use the PASADENA (parahydrogen and synthesis allow dramatically enhanced nuclear alignment) method to achieve 13C polarization of ∼20% in seconds in 1-13C-succinic-d2 acid. The high-field 13C multiplets are observed as a function of pH, and the line broadening of C1 is pronounced in the region of the pK values. The 2JCH, 3JCH, and 3JHH couplings needed for spin order transfer vary with pH and are best resolved at low pH leading to our use of pH ∼3 for both the molecular addition of parahydrogen to 1-13C-fumaric acid-d2 and the subsequent transfer of spin order from the nascent protons to C1 of the succinic acid product. The methods described here may generalize to hyperpolarization of other carboxylic acids. The C1 spin-lattice relaxation time at neutral pH and 4.7 T is measured as 27 s in H2O and 56 s in D2O. Together with known rates of succinate uptake in kidneys, this allows an estimate of the prospects for the molecular spectroscopy of metabolism.
AB - We use the PASADENA (parahydrogen and synthesis allow dramatically enhanced nuclear alignment) method to achieve 13C polarization of ∼20% in seconds in 1-13C-succinic-d2 acid. The high-field 13C multiplets are observed as a function of pH, and the line broadening of C1 is pronounced in the region of the pK values. The 2JCH, 3JCH, and 3JHH couplings needed for spin order transfer vary with pH and are best resolved at low pH leading to our use of pH ∼3 for both the molecular addition of parahydrogen to 1-13C-fumaric acid-d2 and the subsequent transfer of spin order from the nascent protons to C1 of the succinic acid product. The methods described here may generalize to hyperpolarization of other carboxylic acids. The C1 spin-lattice relaxation time at neutral pH and 4.7 T is measured as 27 s in H2O and 56 s in D2O. Together with known rates of succinate uptake in kidneys, this allows an estimate of the prospects for the molecular spectroscopy of metabolism.
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U2 - 10.1021/ja7101218
DO - 10.1021/ja7101218
M3 - Article
C2 - 18335934
AN - SCOPUS:41549109367
SN - 0002-7863
VL - 130
SP - 4212
EP - 4213
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 13
ER -