Meso-Tetraphenylporphyrin Dimer Derivative as a Potential Photosensitizer in Photodynamic Therapy

Abstract— Studies on the synthesis, preliminary in vivo biological activity, singlet oxygen and fluorescence yields of a di-meric porphyrin (Dl) are described. The pharmacokinetic behavior and photodynamic properties of the dimer Dl were examined in Balb/c mice bearing an MS-2 fibrosarcoma. Compound Dl shows a high selectivity for tumor localization (tumor/peritumoral tissue ratios of dye concentration ranging between ca 100 and 140 at 24 h after drug administration of 5.0-1.0 mg kg_-1 into DL-AL-dipalmitoylphosphatidylcholine liposomes). The photo-therapeutic efficiency of dimer Dl was evaluated by following the growth curves of fibrosarcoma irradiated with red light (600-700 nm) with a total dose of 400 J cm_-2, at 24 h after intravenous injection. Photodynamic therapy-treated tumors showed a significant delay in growth as compared to untreated control mice. The results obtained suggest that the porphyrin dimer Dl may be a promising candidate for further use in PDT experiments.