Rapid Transmembrane Exchange of Hyperpolarized 13C-Urea: Pathology-Methods Development Using Erythrocytes

Guilhem Pages¹, Yee Ling Tan¹, Philip William Kuchel¹

Dynamic Nuclear Polarization (DNP) has opened up new avenues to characterize metabolism; we have extended it to study rapid membrane transport of a solute. We used hyperpolarized ¹³C-urea in the presence of urease in erythrocyte suspensions. We designed an extensive kinetic model, taking into account all chemical and transport reactions of the hyperpolarized urea and its products to extract estimates of rate constants of the reactions. The systems urea/urease and urea/erythrocytes were fully characterized with the detection of all chemical species. The success of this In Vitro study albeit on a simple cell-type augurs well for similar in vivo experiments.