Phthalocyanine-cRGD conjugate: synthesis, photophysical properties and in vitro biological activity for targeting photodynamic therapy.

An unsymmetrical phthalocyanine conjugated with an RGDyK moiety (6) was synthesized and characterized. Its photophysical properties, including electronic absorption, fluorescence emission (ΦF = 0.20), singlet oxygen quantum yield (ΦΔ = 0.63) and two-photon absorption cross section (TPACS) at different wavelengths were studied. The in vitro cell study data demonstrate that this Pc conjugate possesses significantly high cellular uptake toward the ανβ3 positive DU145 prostate cancer cells along with an efficient photocytotoxicity (IC50 = 0.04 μM), showing this compound is one of the most promising photosensitizers for targeting photodynamic therapy (PDT) of cancer.