Preparation of astragaloside IV self-microemulsifying drug delivery system and in situ intestinal absorption in rats / 中草药

ABSTRACT

Objective: To prepare astragaloside IV self-emulsifying drug release system (astragaloside IV SMEDDS), and investigate its intestinal absorption characteristics in rats. Methods: According to the solubility and compatibility of astragaloside IV in different oil phases, surfactants and cosurfactants, the prescription composition of astragaloside IV SMEDDS was determined. The dosage range of each component in the ideal microemulsion region was drawn by pseudo-ternary phase diagram, and the microstructure, particle size distribution and in vitro drug release of astragaloside IV SMEDDS after water dispersion were evaluated. The stability of astragaloside IV SMEDDS diluted with simulated human physiological body fluid was investigated, and the intestinal absorption kinetics of astragaloside IV self-microemulsion in rats was investigated by intestinal reflux test in rats. Results: The prescription of astragaloside IV SMEDDS was composed of Capmul MCM, Tween-80, and Transcutol H. Astragaloside IV SMEDDS was prepared by water dispersion to form a light blue emulsion microemulsion, and the uniform size of the microemulsion could be observed under transmission electron microscope, and the microemulsion was prepared by selecting a certain amount of astragaloside IV in any prescription dosage in the microemulsion formation region. The light blue emulsion microemulsion could be observed under transmission electron microscope. The average particle size of astragaloside IV SMEDDS was (45.4 ± 5.8) nm; The dissolution rate of astragaloside IV in the three dissolution media was significantly increased, and the microemulsion formed by astragaloside IV had good physical stability in simulated human physiological liquid. The absorption rate of astragaloside IV microemulsion in the whole intestine of rats was significantly higher than that of astragaloside IV suspension. Conclusion: The preparation of astragaloside IV into SMEDDS can increase the dissolution rate of the drug, enhance the absorption of the drug in the intestinal tract, which is expected to improve the oral bioavailability of astragaloside IV.