Korenchan, D.E., et al., Dynamic nuclear polarization of biocompatible (13)C-enriched carbonates for in vivo pH imaging. Chem Commun (Camb), 2016. 52(14): p. 3030-3.
http://www.ncbi.nlm.nih.gov/pubmed/26792559
A hyperpolarization technique using carbonate precursors of biocompatible molecules was found to yield high concentrations of hyperpolarized (13)C bicarbonate in solution. This approach enabled large signal gains for low-toxicity hyperpolarized (13)C pH imaging in a phantom and in vivo in a murine model of prostate cancer.