Objective: To select the best formula and technology for the preparation of scutellarin sustained-release microspheres and study on its pharmaceutical properties. Method: S/O/W emulsification solvent evaporation method was adopted to prepare scutellarin sustained-release microspheres

taking composite score of drug loading

encapsulation efficiency and yield as index

orthogonal test was used to optimize preparation process of scutellarin sustained-release microspheres and its in vitro release was investigated.This microspheres was charaterized in some ways

such as laser particle size analyzer

scanning electron microscopy

Fourier transform infrared spectroscopy and X-ray diffraction. Result: Optimum preparation process was as following:scutellarin dosage of 25 mg

poly(lactide-glycolide acid) (PLGA) amount of 200 mg

polyvinyl alcohol (PVA) amount of 1.0%

dichloromethane-acetone (1.7:0.3)

stirring speed of 1 000 r·min-1.The drug loading

encapsulation efficiency and yield were (6.18±0.11)%

(50.79±2.01)% and (91.18±2.19)%

respectively;in vitro cumulative release of 30% needed ≥600 h

average particle size was (126.0±2.10) μm.The surface of scutellarin sustained-release microspheres was round without adhesion.The internal of microspheres had some crystals of scutellarin.FT-IR and XRD indicated that scutellarin still existed in the form of crystals. Conclusion: Sustained-release microspheres of scutellarin is successfully prepared with emulsification solvent evaporation method.This optimized process is simple and reasonable

which is basis for further research of scutellarin preparations.