Application of the Steady-state Variable Nutation Angle Method for Faster Determinations of Long T 1 S–-an Approach Useful for the Design of Hyperpolarized Mr Molecular Probes

Abstract

In the dissolution-dynamic nuclear polarization technique, molecular probes with long T 1 s are preferred. 13 C nuclei of small molecules with no directly bonded protons or sp 3 13 C nuclei with proton positions substituted by deuterons may fulfill this requirement. The T 1 determination of such new molecular probes is crucial for the success of the hyperpolarized observation. Although the inversion-recovery approach remained by and large the standard for T 1 measurements, we show here that the steady-state variable nutation angle approach is faster and may be better suited for the determination of relatively long T 1 s in thermal equilibrium. Specifically, the T 1 of a new molecular probe, [uniformly labeled (UL)- 13 C 6 , UL- 2 H 8 ]2-deoxy-d-glucose, is determined here and compared to that of [UL- 13 C 6 , UL- 2 H 7 ]d-glucose.