CONJUGUÉ PHOTOSENSIBILISANT-PEPTIDE COMPRENANT UNE SÉQUENCE DE LIAISON DÉGRADABLE, ET COMPOSITION POUR DIAGNOSTIC OU TRAITEMENT PHOTODYNAMIQUE COMPRENANT LEDIT CONJUGUÉ
The present invention relates to a conjugate for photodynamic diagnosis or treatment in which a peptide binds with a photosensitizer via an intracellularly degradable linkage, and to a composition for photodynamic diagnosis or treatment including the same. The conjugate of the present invention generates no fluorescent signal and reactive oxygen in normal tissues or during the circulation in the blood by quenching a fluorescent signal and reactive oxygen generation ability of the photosensitizer. After the conjugate is selectively absorbed into target cells, a linker is degraded in the cells to increase the distance between tryptophan included in the peptide and the photosensitizer, and the quenching action is terminated to generate a strong fluorescence signal and induce active generation of reactive oxygen. Therefore, the conjugate according to the present invention has high tissue permeability, shows a high photodynamic therapeutic effect in only target cells while being safe in normal cells, and can obtain a good diagnostic image having a high ratio of target signal to background.
