Novel Chlorine E6 Conjugate with Dual Targeting to Cancer Cells

Photodynamic therapy (PDT) has been successfully used to treat many types of tumors. However, the widespread use of PDT is limited by a number of factors, including low selectivity of photosensitizer (PS) accumulation in tumor tissue. We have synthesized the novel third-generation photosensitizer, conjugate of zinc complex of chlorine e6 with maltose and biotin (Chl-Mal-B₇). The introduction of maltose and biotin is intended to provide high selectivity to tumor cells often characterized by high-level expression of receptors for these molecules. It was shown that Chl-Mal-B₇ intensively absorbs light and fluoresces in a far-red spectral region with a quantum yield of about 10%. Chl-Mal-B7 demonstrated photoinduced toxicity in submicromolar concentrations against cancer cells that is several times more effective compared to nonmalignant cells.