Study on Preparation and Drug Release in vitro of Norcantharidin-chitosan-silk-fibroin Microspheres

Objective: To study the Norcantharidin-chitosan-silk fibroin microspheres (NCTD-CS-SF-MS) for transcatheter arterial chemoembolization(TACE) by using chitosan(CS)and silk fibroin(SF) as carriers and norcantharidin (NCTD) as model medicine,based on the excellent plasticity of CS and the biocompatibility of SF.To study the drug loading,envelop efficiency and the surface morphology of the microspheres,and to determine the release characteristic of norcantharidin from microspheres in vitro.Methods: NCTD-CS-SF-MS was carried out by emulsifying cross-linking process with liquid paraffin as oil phase,the hybrid of CS and SF as water phase,Span-80 as emulsifier,and glutaraldehyde as cross linking agent.The central composite design was applied to optimize the formulation and preparation procedure.The surface morphology of the microspheres was observed under scanning electron microscope (SEM),the interaction of the drug and the polymer was analyzed by X-RD and DSC,and dynamic dialysismethod was used to determine the release characteristic of norcantharidin from microspheres in vitro.Results: Novel microsphere with a global shape and narrow distribution were prepared.The average diameter was about (184.0± 5.0) μm,the drug loading rate was (15.08±2.85)%,and the envelop efficiency of microspheres was (27.46±1.25)%.The drug release behavior at 0.1 mol/L HCl,phosphate buffered saline (pH =7.4) and physiological saline conformed Weibull distribution model.Conclusion: The optimized preparation technique was feasible,and microspheres with high drug-loading rate and evident effect of sustained drug release were prepared.