Photodynamic Effect of Amphiphilic NCN-Coordinated Platinum(II) Complexes in Human Umbilical Vein Endothelial Cells.

Here, we report a photodynamic therapy (PDT) photosensitizer of NCN-coordinated Pt(II) complexes: [Pt(L)(solv)] (HL = 1,3-(2-dipyridyl)benzene) and [Pt(L)]@HSA, which is the Pt(II) complex encapsulated in human serum albumin (HSA). The quantum yield of singlet oxygen production for [Pt(L)(solv)] is more than 50%, while that for [Pt(L)]@HSA is much lower. Photoimages of human umbilical vein endothelial cells (HUVECs) treated with the Pt(II) complexes suggest that [Pt(L)(solv)] is delocalized in the entire cell after the fast uptake by diffusion and [Pt(L)]@HSA is taken up by endocytosis and localized on organelles and the cell membrane. [Pt(L)(solv)] shows high photocytotoxicity for HUVECs, while [Pt(L)]@HSA does not show photocytotoxicity.