Abstract

Ligustrazine phosphate is commonly used as an efficient drug to treat a variety of cardiovascular disorders with frequent administration for a short biological half-life. The purpose of the present study was to investigate a microemulsion system for transdermal delivery of ligustrazine phosphate for the convenient, efficient and safe administration. The existence regions of microemulsions containing isopropyl myristate, labrasol, plurol oleique^®and water were investigated in pseudo-ternary phase diagrams, according to which microemulsion vehicles were prepared to observe average diameter, pH value, stability and evaluate respective effect of each component on percutaneous delivery in vitro. The prepared microemulsions had average diameters ranging from 32.1 to 108.7 nm, mild pH values and suitable stability. The optimized microemulsion with permeation flux of 41.01 μg/cm²/h across rat skin in vitro, showed no obvious irritation on back skin of rabbits. The results indicated that the studied microemulsion system might be a promising vehicle for transdermal delivery of ligustrazine phosphate.

Key words: Microemulsion, transdermal delivery, ligustrazine phosphate.