All four DMDPA derivatives exhibited significantly lower heart/liver radioactivity uptake ratios (0.6, 0.4, 0.7 and 0.6, respectively) compared to that of DMDPA (1.2). The other two were labeled using carbon-11: methyl-(3-fluorophenyl)-methylphenylammonium trifluoromethanesulfonate (3-F-DMDPA) and methyl-(4-fluorophenyl)-methylphenylammonium trifluoromethanesulfonate (4-F-DMDPA). Four fluorinated DMDPA derivatives were synthesized, two were labeled with fluorine-18: fluoroethyl-methyldiphenylammonium trifluoromethanesulfonate (FEMDPA) and fluorobuthyl-methyldiphenylammonium trifluoromethanesulfonate (FBMDPA). Organ uptake after injection of fluoroethylquinolinium acetate (FEtQ) was examined ex vivo. The dynamic distribution in vivo, following injection of each derivative into male SD rats, was evaluated using small-animal dedicated PET/CT.
Four fluorinated DMDPA derivatives and two quinolinium salt analogs were radiolabeled. The current study aimed to increase the clinical applicability of PET-MPI by designing and synthesizing fluorinated ammonium salt derivatives. We previously presented the radiolabeled ammonium salt -dimethyl diphenylammonium trifluoromethanesulfonate (DMDPA) as a potential novel PET-MPI agent.