Basic study on different co-surfactant O/W pharmaceutical microemulsions

OBJECTIVE To study the relationship between different co-surfactant and the formation of nanoemulsion.METHODS Titrimetric method was used for drawing pseudo-ternary phase diagrams to inspect the formation influence caused by different co-surfactant on the microemulsions.RESULTS when the surfactant and oil phase situation were the same,the different structure and nature of different co-surfactant,quality ratio(Km)of surfactant and co-surfactan as well as the temperature changes would influence the formation of nanoemulsion.CONCLUSION Under the appropriate condition,the amount of surfactant in the microemulsion system can be reduced by choosing the right kind of surfactant and appropriate oil phase,with the helps of right kind of co-surfactant and its amount.Moreover,in general,the region size of the microemulsions has positive relationship with the total amount of surfactant and co-surfactant,and has negative relationship with the oil and co-surfactant amont.So it is not enough to determine the most excellent formation condition of pharmaceutical microemulsions only by using drawing pseudo-ternary phase diagrams,it is necessary to conduct the stability inspection of microemulsions.