Synthesis and evaluation of Tc/Re-tricarbonyl complexes of the triphenylphosphonium cation for mitochondrial targeting.

Introduction: Lipophilic delocalized cations accumulate in tumor cell mitochondria due to their higher transmembrane potential. In this work, this strategy was adopted for the development of Tc tumor-targeted imaging agents.

Methods: Two tridentate ligands containing the triphenylphosphonium cation, L1 (S-cysteinyl) and L2 (N-iminodiacetate) as well as the respective Tc/ReL1 and Tc/ReL2 tricarbonyl complexes were synthesized.