| Objective:Prepare functional oxide graphene nano-carrier(NGO-PEG),loading oridonin(ORI),and study the anticancer offect in vitro.Methods:In order to prepare NGO-PEG,4-armed PEG was grafted onto NGO via an amidation process.NGO-PEG was characterized by UV,FLU,IR,DSC-TGA,AFM,DLS,Stability test,Zeta potential determination.In order to prepare ORI/NGO-PEG,ORI was loaded on NGO-PEG by non covalent adsorption.ORI/NGO-PEG was characterized by AFM,DLS,Stability test,Zeta potential determination,take medicine experiment,drug release.SW620 and HT-29 colon cancer cell were chosen to study the cytotoxicity of ORI/NGO-PEG,NGO-PEG,and free oridonin.Results:NGO-PEG appeared at 227nm ultraviolet absorption peak is weaker than NGO,appeared at 530nm in fluorescence emission peak intensity is weaker than NGO,appeared strong infrared absorption peak in 2900cm-1.NGO-PEG occurred weight loss within the temperature scope of 130℃ to 210℃ and 350℃ to 450℃ respectively,corresponding at 185℃ and 421℃ an exothermic peak.When the temperature reached 500℃,the weightlessness rate of NGO was 35.48%,the weightlessness rate of PEG was 98.70%,the weightlessness rate of NGO-PEG was 71.91%.NGO-PEG was the piece of layered planar structures,and the thickness was 1.2nm,ORI/NGO-PEG was the shape of the present middle thick,thin edge,and the thickness was 31.2nm.The average particle size of NGO-PEG was 240±10nm,and the average particle size of ORI/NGO-PEG was 258±12nm.The stability test indicated excellent dispersibility of NGO-PEG and ORI/NGO-PEG in water,0.9%NaCl,PBS and Cell medium.The zeta potential of NGO-PEG was-16.1±1.6mV,and the zeta potential of ORI/NGO-PEG was-38.3±1.3mV.The drug loading ratio was 95.81%.The rate of release ORI in acid environment was faster than in a neutral environment.The SW620 and HT-29 colon cancer cells survival rate was above 80%basically after NGO-PEG train to 24h.The Cell survival rate was no significant difference after ORI/NGO-PEG and ORI train to 24h.Conclusion:The PEG had been successfully modified on NGO,preparing NGO-PEG,which had good dispersion stability.The quality ratio between NGO and PEG was 1:1.36.PEG modification did not change the particle size of NGO.ORI had been successfully loaded on NGO-PEG,preparing ORI/NGO-PEG,which had good dispersion stability.NGO-PEG had higher drug-loading rate to ORI.ORI/NGO-PEG could be used as a pH sensitive drug delivery system.NGO-PEG was low toxicity to SW620 and HT-29 colon cancer cells,and would not affect the anticancer activity of ORI. |
