Radachlorin labeled Gallium-68 Pharmaceutical: a New Theranostic Agent for the Integration of Photodynamic Therapy and Nuclear Imaging

The cyclic tetrapyrrolic compounds, such as porphyrins, play an important role in medical research due to their fundamental role in the body of living beings, the ability to accumulate in various human cancer cells, as well as having distinct physical, magnetic, and optical properties. Therefore, they are very useful in the design of anticancer pharmaceuticals and photodynamic therapy agents. Due to the prominent properties of gallium -68 and the targeted accumulation of radachlorin anticancer drug, the radiopharmaceutical complex of this porphyrin is synthesized with gallium -68 radionuclide and its biological information such as partition coefficient and biodistribution studies in normal and tumorbearing rats were studied. The complex was prepared with acceptable radiochemical purity and stability in the final formulation and human serum for 4 h. The partition coefficient was -1.14. High accumulation of the complex in the tumor, rapid washout from the body, and lower absorbed radiation doses to patients were observed using this labeled compound. In this study combining the unique reactivity of gallium -68 with flat-lipophilic ligands with a neutral electric charge, such as radachlorin, the potential for beta excretion for PET, and the use of radachlorin in PDT for therapeutic purposes, a new PET / PDT imaging agent was introduced.