A novel of PEG-conjugated phthalocyanine and evaluation of its photocytotoxicity and antibacterial properties for photodynamic therapy

A poly(ethylene glycol) (PEG)-conjugated silicon(IV) phthalocyanine axially substituted with (PEG1000) chains (SiPc-PEG) was synthesized, and this novel phthalocyanine was characterized by 1H-NMR, FT-IR and UV-Vis spectrophotometric methods. Elemental analysis data were beneficial for the evaluation of the chemical structure of the new compound. The total number of (O–CH2–CH2 units was calculated as 44 and the structure of the new PEG-conjugated silicon phthalocyanine was determined by the use of integral areas in 1H-NMR spectrum and the ratio of SiPc:PEG1000 was found as 1:2. The photophysical and photochemical properties were determined in both DMSO and aqueous solutions. In addition, the photocytotoxicity of the novel PEG-conjugated silicon(IV) phthalocyanine wasalso examined by testing against human cervical-carcinoma (HeLa) and hepato-carcinoma cells (HuH-7). The IC50 value for the SiPc-PEG compound was determined as 0.28 μM for HeLa cells and 0.4μM for HuH-7 cells. These results imply that HeLa cell...