ABSTRACT
Objective To prepare PEGylated graphene oxide nanoparticles (GO-PEG-NPs) loaded with oridonin (ORI) and investigate its inhibitory effect on human colon cancer. Methods 4-armed PEG was grafted onto GO via an amidation process and GO-PEG was characterized by IR and TGA. Then, ORI, a widely used cancer chemotherapy drug, was absorbed onto GO-PEG via blending. The encapsulation efficiency and drug loading ratio were measured by UV. The cytotoxicity of ORI-GO-PEG, GO-PEG, and free ORI on SW620 and HT29 human colon cancer cells were evaluated using MTT assay. In vivo anti-tumor activity of ORI-GO-PEG-NPs were evaluated in mice bearing SW620 tumor. Results IR and TGA data indicated that 4-armed PEG was successfully coupled with GO and UV data showed that the encapsulation efficiency and drug loading ratio were 95.81% and 48.92%, respectively. Moreover, ORI-GO-PEG-NPs showed good stability in physiological condition. The results of cytotoxicity test indicated that compared to free ORI, the ORI-GO-PEG-NPs exhibited higher cytotoxicity in SW620 and HT29 cells. Meanwhile, it was confirmed that ORI-GO-PEG- NPs could significantly inhibit the growth of SW620 tumor in vivo compared with ORI. Conclusion The obtained ORI-GO-PEG-NPs displayed excellent drug-loading capacity and better tumor inhibitory effect. These results provided the experimental basis for development of anticancer drug delivery system.