Measurement of tumor extracellular pH (pHe) by a PET/MRI co-inject reagent

Motivation: The measurement of extracellular pH (pHe) is very important for studying the cancer development, progression, and therapeutic response. Goal(s): Accurately measure the pHe for 4T1 tumor and 0.2 pH change in vitro independent on the concentration of MRI contrast reagent. Approach: To co-inject the synthesized pH sensitive MRI contrast reagent and the PET reagent with the same pharmacokinetic functions and DCE MRI and dynamic PET scan were obtained simultaneously. Results: The pHe change of the bicarbonate treatment for the acidosis tumor type can be measured by our PET/MRI co-inject reagent. Impact: PET/MRI co-inject reagent makes it possible for the pHe measurement independent of the concentration of MRI contrast reagent.