Study Of Graphene Oxide And Hyaluronic Acid Modified Particles As A Carrier For Combretastain A-4 Derivatives

The graphene oxide(GO)particles were prepared successfully using the improved method of Hummer.Scanning electron microscopy(SEM)observations show that the particles possess the grain flake morphology with the size range of200~400nm and steadily layer structure,which is good for the loading of drugs.The analysis results of dynamic light scattering showed that the average size of the as-prepared particle is 240 nm,which is consistent with the scanningn electron microscopy observation,and Zeta potential of the particles is about-40 mV.The GO particles were used as drug carrier of combretastain derivatives(CA–4P),which is the tumor vascular drug for second generation.The drug release in vitro was explored under different pH.The results show that the encapsulation rate of the drug for GO can reach 72.59%,and the release rate is 20.34%,the loading amount of the drug is0.581 mg/mg.The adsorption behavior was analysied by Langmuir and Freundlich model,and the results show that the drug adsorbtion of GO is more accord with the Freundlich model,The experimental study in vitro release found that,the drug release rate in acid conditions is about 62.53%,while it is 34.4% in neutral environment.The mechanism in vitro release of CA-4P can be explained by Fickian diffusion process.The hyaluronic acid grafted graphene oxide particles(GOP-HA)was prepared with the hyaluronic acid(HA)as targeting ligand,which was covalently bonded to the surface of the graphene oxide modifed with the polyethyleneimine(PEI).The results of FI-IR,XRD and TGA measurment show that,the hyaluronic acid was successfully grafted to the surface of graphene oxide,and the amount of grafting polymer into the total component was accounted for 34%.SEM and DLS analysis showed the layer structure morphology of the particles was stable,indicatingg that the GO amination and grafting do not impact on the as-prepared particle morphology.The average particle size is 400 nm through dynamic light scattering determining,its size is bigger than that of the GO particle size.The GOP-HA was used as the drug carrier of combretastain derivatives(CA–4P),which is the tumor vascular drug for second generation.The drug release in vitro was explored under different pH,and the results show that the GOP-HA was used as drug carrier of CA–4P,the encapsulation rate canreach 65.60%,and the loading rate was 16.36%,the drug amount loaded is 0.309mg/mg.The in vitro release experiments show that the drug release rate was higher in acid environment,and the release rate is 57.82%.The adsorption process of the drug can explain the Freundlich adsorption model.The in vitro release process of CA–4P drug is conformed to Fickian diffusion mechanism.