Increasing the hyperpolarization level on PHIP-SAH polarized pyruvate in a fully biocompatible solution.

Hyperpolarized 1-13Cpyruvate can be obtained by means of ParaHydrogen Induced Polarization-Side Arm Hydrogenation, a hyperpolarization technique that is significantly more cost effective and faster than the gold-standard method d-DNP. The hyperpolarization level that we reported previously, for the fully biocompatible aqueous solution of this HP metabolite, was sufficient to carry out metabolic studies, but still low. In this work we show that the use of a lower catalyst concentration, together with a co-catalyst, and an improved magnetic field cycle profile for spin order transfer can double the HP level on this metabolite.