Vitamin B_c-Bearing Hydrophilic Photosensitizer Conjugate for Photodynamic Cancer Theranostics

The accurate diagnosis and proper therapy for cancer are essential to improve the success rate of cancer treatment. Here, we demonstrated that the vitamin B_c-bearing hydrophilic photosensitizer conjugate folic acid-polyethylene glycol-pheophorbideA (FA-PEG-PheoA) has been synthesized for the intracellular diagnosis and photodynamic therapy of a tumor. The synthesized vitamin B_c-bearing hydrophilic photosensitizer conjugate has been characterized for the folic acid receptor expressing the ability to target tumor cells, which is facilitated by the chemical conjugation with folic acid. The vitamin B_c-bearing hydrophilic photosensitizer conjugate internalization mechanism was identified through a competitive inhibition test with free folic acid. We optimized the laser-sensitive, cytotoxicity changeable, vitamin B_c-bearing hydrophilic photosensitizer conjugate concentration, which is non-cytotoxic under normal conditions and specifically cytotoxic toward cancer cells (maximum 69.15%) under laser irradiation conditions used for theranostic agents. The cancer therapeutic and diagnosis effects of synthesized conjugate were confirmed in MDA-MB-231 cells and MDA-MB-231-bearing mice. As a result, the vitamin B_c-bearing hydrophilic photosensitizer conjugate exhibited a highly photodynamic therapeutic effect, which enabled the selective detection of a folic acid receptor expressing cancer using optical imaging. A Vitamin B_c-bearing hydrophilic photosensitizer conjugate, folic acid-polyethylene glycol-pheophorbideA (FA-PEG-PheoA), is synthesized for photodynamic cancer theranostics. By conjugating FA with a photosensitizer that can be used in optical imaging and further clinical treatment, FA-PEG-PheoA is delivered to the FA receptor overexpressing cancer and utilized for cancer diagnosis and therapy simultaneously.