Cucurbita pepo oil as a drug microemulsion formulation: study of phase diagram


1 Department of Chemistry, Urmia Payamnoor University, Urmia, Iran

2 Department of Pharmaceutical Nanotechnology, Tabriz University of Medical Science, Tabriz, Iran

3 Pharmaceutical Nanotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.



Investigation of phase diagram of various drug formulations is effective to predict different phase region of drugs to detect final formula. The purpose of this research was to develop the ternary phase diagrams for a drug microemulsion system consisting of Cucurbita pepo (pumpkin) oil, surfactant (Tween 80) and deionized water.
Materials and Methods:
An electrical conductivity was used to study the properties of system. Particle size analysis of microemulsion system was performed by dynamic light scattering.

The electrical conductivity of the microemulsions increases with increasing of aqueous phase content. Structural transitions from the oil-in-water to a bi-continuous phase then inversion to water-in-oil occured in the system. Diameter of particles was calculated 70 nm (for 75 percent of particles) and 35 nm (for 25 percent of particles).  Solubility results showed that microemulsion system of Cucurbita pepo oil can increase its solubility in aqueous medium due to droplet size reduction into nanometer size.
Microemulsion technique can be used as a successful method in preparation of Cucurbita pepo oil drug formulation.


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