Synthesis and biological evaluation of ⁶⁸Ga-NOTA-porphyrin: a potential agent for PET imaging of tumorous lesions

Radiolabeled porphyrins have the ability to preferentially localize in neoplastic tissues and thus can be useful in tumor diagnosis or targeted tumor therapy. In the present study, the potential of a ⁶⁸Ga-labeled porphyrin derivative, namely 5,10,15,20-tetrakis (p-carboxymethyleneoxyphenyl)porphyrin has been explored towards its possible application for PET imaging of tumorous lesions. The porphyrin derivative, synthesized in-house, was coupled with a bi-functional chelating agent (p-NH₂-benzyl-NOTA) and radiolabeled with ⁶⁸Ga, obtained from a ⁶⁸Ge/⁶⁸Ga generator. Bioevaluation studies carried out in tumor bearing Swiss mice showed encouraging uptake in tumorous lesions with favorable target to non-target ratios which provided early evidence towards the potential of the ⁶⁸Ga-labeled porphyrin derivative. (author)