13C hyperpolarization of a barbituric acid derivative via parahydrogen induced polarization

On the spin order transfer from parahydrogen to another nucleus

“…For the sake of consistency, we use h G . Two cases apply for the molecules considered here: Again, a relatively ''simple'' sequence (case 2a, 35.3°< h G 6 65.7°, Eq. (4), Fig.…”

“…When the sequence was applied previously, a range rather than specific values were used for the intervals [35]. No polarization yields or expressions to obtain optimal SOT parameters are described.…”

Creation and evolution of net proton hyperpolarization arising from para-hydrogenation

“…We shall make the approximation that this small angle read-pulse does not significantly affect the evolution of the different spin states appearing subsequently to sequence (6 Fig. 5.…”

“…Indeed, the problem is to transform the proton spin state into 13 C hyperpolarization. A first approach is an INEPT-like pulse sequence [3][4][5][6]. Field cycling procedures [2,7] or special pulse sequences [8,9] constitute other ways of achieving 13 C hyperpolarization by transfer from enhanced proton spin states.…”

ParaHydrogen Induced Polarization of 13C carboxylate resonance in acetate and pyruvate

“…Among them, succinate 14,15 and phospho-lactate 16,17 are the only metabolites for which good hyperpolarization level has been achieved until now. Alternative routes have been proposed to achieve PHIP on biologically relevant molecules by functionalizing the substrates of interest with moieties capable of hydrogenation [18][19][20] . However, the structural modifications introduced by the unsaturated group may significantly alter their biological behaviour with respect to the native substrates.…”