Objective    To prepare an ethosomal delivery system containing mouse epidermal growth factor (mEGF) and investigate its entrapment efficiency and physical properties.     Methods    The entrapment efficiency of mEGF ethosome (10 μg/g) was determined by high pressure liquid chromatography (HPLC). The mEGF ethosome vesicles were visualized by scanning electron microscopy (SEM)

atomic force microscopy (AFM) and transmission electron microscopy (TEM). And the size distribution of ethosome vesicles was investigated using dynamic light scattering (DLS).     Results     The mEGF ethosome had an entrapment efficiency of 38% and the RSD was less than 5%. The entrapment efficiency of mEGF ethosomal carriers ranged from 36% to 38% during 30 d after having been prepared. mEGF ethosomal carriers had rather small vesicles in a size ranging from 40 nm to 60 nm visualized by AFM and TEM. And the size of the mEGF ethosomal delivery system had uniform distribution ranging from 100 nm to 500 nm. Also

the refractive index of the mEGF ethosomal delivery system was 4.6.     Conclusion    A mEGF ethosomal delivery system is successfully prepared. A HPLC method is developed to determine mEGF content in ethosomal delivery system. The delivery system shows a well stability and a narrow particle size distribution.