A Galactose Dendritic Silicon (IV) Phthalocyanine as a Photosensitizing Agent in Cancer Photodynamic Therapy.

Two protected galacto-dendritic units have been axially coordinated to the central ion of a silicon(IV) phthalocyanine to afford SiPcPGal₄ containing four units of galactose per macrocycle. These biological moieties provided better solubility in aqueous medium and a sensitizer with higher absorption peaks at 680-690 nm. The photodynamic activity of SiPcPGal₄ was evaluated against UM-UC-3 human bladder cancer cell line and the results were compared with the activity of the reported SiPcPGal₂ and SiPc(OH)₂ . SiPcPGal₄ had a better uptake and it was a better toxicity inducer than SiPcPGal₂ and SiPc(OH)₂ owing to its four galactose units, protected by isopropylidene groups, which can act as targeted micelles.