▎ 摘　　要

The aim of this study is to synthesize graphene oxide (GO) nanocomposites conjugated with chlorin e6 (Ce6) and methoxy poly(ethylene glycol) (MePEG) using disulfide linkage for photodynamic treatment of cholangiocarcinoma (CCA) cells. Graphene oxide was conjugated with MePEG and cystamine (GO-(NSSNH2)-PEG). After that, amine end group was further conjugated with Ce6. Ce6 and MePEG conjugated GO nanocomposites (GO NP) were characterized and its photodynamic effect was studied with various CCA cells. In morphological observation, GO NP formed nano-aggregates with small sizes less than 100 nm while GO itself showed typical sheet shape. Ce6 release from GO NP was faster in the presence of glutathione, indicating that GO NP has redox-responsiveness. GO NP showed significantly higher intracellular Ce6 uptake ratio and produced higher amount of ROS than Ce6 itself. Then, GO NP resulted in increased anticancer activity against CCA cells compared to Ce6 itself. In animal study with SNU478 cell-bearing mice, GO NP was properly concentrated in tumor tissue while Ce6 treatment showed relatively higher fluorescence intensity in liver than that of tumor tissue. Tumor growth was significantly inhibited by treatment of GO NP with irradiation compared to Ce6 treatment. GO NP showed redox-responsiveness and increased photodynamic effect against CCA cells. We suggest GO NP as a promising candidate for photodynamic therapy (PDT) of CCA cells.