ABSTRACT
Objective To explore self-emulsifying particle size characterization methods and compare the regularity of various methods. Methods By setting the clarity level of turbidity standard solution, with two less soluble drugs-diterpene lactone compounds Chuanhuning and dihydropyridine drug nifedipine as model drugs, 10-12 clarity level prescriptions were selected from six different ternary phase diagram. Laser particle size scanner was used to determine the particle size, and UV-visible spectrophotometry to determine its absorbance. Three methods of particle size characterization rules were compared by drawing charts. Results There was a positive correlationship among droplet particle size, absorbance and clarity grade of emulsion formed by prescription in the same phase diagram. But, there was no regularity among droplet particle size, absorbance and clarity grade of emulsion formed by prescription in different phase diagram. Conclusion The droplet particle size of emulsion formed by prescription containing the same drugs and excipients in different proportions can be compared by clarity with visual method or absorbance with UV-visible spectrophotometer.