Photodynamic therapy target photosensitizer

Many compounds sensitize biomolecules to damage by UVA (320-380 nm) and visible light. Two general mechanisms of sensitization are encountered. The Type I mechanism involves electron or hydrogen transfer from the target molecule to the photosensitizer in its triplet state. If 02 is present, this can be reduced to 02 by the reduced sensitizer. In the Type II mechanism, the excited sensitizer is quenched by 02, which is excited to the singlet state (typically A"g) and attacks the target molecule. Photosensitization is exploited in photodynamic therapy (PDT) for the destruction of cancerous or other unwanted cells. 

Takeuchi Y et al (2004) Intracellular target for photosensitization in cancer antiangio-genic photodynamic therapy mediated by polycation liposome. J Control Release 97 231-240... 

Two-Color Two-Laser DNA Damaging Photodynamic therapy (PDT) is a promising treatment for cancer based on the photosensitized oxidative reaction at the diseased tissues producing cell death, and DNA is considered as a potential target [122]. Compared with surgery and chemotherapy, the... 

One of the major side effects of these first generation photosensitizers is prolonged skin photosensitivity, requiring sun and light protection for 1-2 months. Another interesting approach utilises antibody-targeted photodynamic therapy. The use of zinc phthalocyanine antibody-MCA complex improved tumor selectivity, avoided skin phototoxicity and resulted in partial remission of the chest wall metas-tases [17]. 

Trachtenberg J, Bogaards A, Weersink RA, Haider MA, Evans A, McCluskey SA, Scherz A, Gertner MR, Yue C, Appu S, Aprikian A, Savard J, Wilson BC, Elhilali M. Vascular targeted photodynamic therapy with palladium-bacteriopheophorbide photosensitizer for recurrent prostate cancer following definitive radiation therapy Assessment of safety and treatment response. J Urol 2007 178 1974—1979. 

Tumor targeting in photodynamic therapy. From glycoconjugated photosensitizers to glycodendrimeric one. Concept, design and properties 120BC4485. 

Chen, J. C. Photodynamic therapy comprising administration of a targeted photosensitizing agent, for treatment for eye disease such as diabetic retinopathy, macular degeneration, and malignant uveal melanomas. U.S. Patent 7320786, 2008 Chem. Abstr. 2008, 148, 152083. 

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