13C nmr spectroscopy: relaxation times of 13C and methods for sensitivity enhancement

Application of Relaxation Dispersion of Hyperpolarized 13C Spins to Protein–Ligand Binding

“…Since the curves in Figure 4 b and c do not plateau at the shortest pulsing time, the lifetime of TFBC binding to trypsin t b is not unambiguously determined. The curves are, however, consistent with the previous 19 F relaxation dispersion measurement of TFBC in the presence of trypsin, where a t b value of 0.3 ms was found. [17] The lower limit of the pulsing delay (right side of the graphs in Figure 4) is primarily governed by the signal acquisition time for each echo, which is required for chemical shift resolution.…”

Dicarboxylic acids as pH sensors for hyperpolarized13C magnetic resonance spectroscopic imaging

“…The T 1 was longer at the higher field strength, as might be expected for a quaternary carbon nucleus dominated by dipole-dipole relaxation. 27 Minimal variation in T 1 was observed over the physiologic pH range (Figure S1). The HP DEMA linewidth broadened due to chemical exchange as pH increased from 6.8 (13.1 Hz) to 7.5 (18.7 Hz), as expected based on the exchange mechanism, which is both acid- and base-catalyzed.…”

Evaluation of enzymatic and magnetic properties of γ-glutamyl-[1-13C]glycine and its deuteration toward longer retention of the hyperpolarized state

“…The ndings that the a-1 H near the 13 C nucleus of g-Glu-[1-13 C]Gly accounted for most of the DD relaxation is consistent with the theoretical explanation that the R 1DD is inversely proportional to the sixth power of the distance between the 1 H and 13 C nuclei. 25,26 These ndings showed that g-Glu-[1- . This result is consistent with the fact that carbonyl 13 C generally exhibits a large relaxation due to the CSA mechanism.…”