Continuous aqueous phase
External phase other name
Continuous phase
Internal phase other name
Disperse
Suitable for IV route and oral route
Oil-in-Water (O/W)
Suitable for topical route, and subQ/IM injections
Water-in-oil (W/O)
Parenteral nutrition
Oil-in-Water (O/W)
Drug carriers Low viscosity
Oil-in-Water (O/W)
Dermatologic emulsions usually use ionic or non-ionic surfactants
Water-in-oil (W/O)
High viscosity
Water-in-oil (W/O)
Medicinal oils for constipation, oral food supplements, vitamins
Oil-in-Water (O/W)
Thermodynamically UNstable
Nanoemulsions
Thermodynamically stable
Microemulsions
Optically clear and transparent
Nanoemulsions
Optically clear and transparent
Microemulsions
Esotropic mixtures of a biphasic o/w system (Ansel’s)
Microemulsions
Dispersions of oil and water (as individual droplets)
Nanoemulsions
single-phase system, “not emulsions” (Aulton’s)
Microemulsions
Anionic surfactant O/W
SLS, Sodium stearate
Anionic surfactant W/O
Calcium oleate
Cationic surfactant
Quaternary Ammonium compounds (Cetrimide) - O/W