Preparation And Antitumor Activity Assays Of Phenanthriplatin Nanocarriers Based On Rare-earth Upconversion Nanocrystals

In recent years, rare earth doped upconversion nanoparticles have gained much attention from biomedicine for using in multifunctional drug delivery systems, which provide simultaneous targeting, diagnostics and therapy within a single system. In this thesis,we report an anticancer drug delivery system based on new drug phenanthriplatin(IV)-conjugated rare earth upconversion nanocrystalline NaGdF4:Yb3+/Er3+. In this dissertation,rare earth doped nanomaterials were synthesized by a high temperature boiling solvent method. And the nanomaterials were modified with branched polyethylenimine(PEI) and combined with the anticancer drug phenanthriplatin, PEG and targeting molecule peptide RGD. The nanomaterials exhibit an obvious cytotoxic effect on U87 MG cells via MTT assay,flow cytometry and Pt-DNA adducts. Meanwhile, the endocytosis process of nanoparticles by U87 MG cells was demonstrated through up-conversion luminescence microscopy,ICP-OES and endocytosis. In addation, the evidences of in vitro and in vivo T1-weighted MR imaging indicate that the nanoparticles could be used as probes for biomedical diagnosis.The in vivo experiments on mice also confirm that the Phen-Pt(IV)-conjugated nanoparticles have relatively high tumor inhibition rate. These results indicate that the multifunctional nanoparticles are expected to be a platform for simultaneous diagnosis and cancer therapeutic applications.