Figure 6.

Common methods for preparing oil-in-water nanoemulsions. (A) The high energy methods, such as high pressure homogenization (HPH) and ultrasonication, break coarse emulsions drops into smaller droplets. (B) The low-energy methods start with W/O coarse emulsions, and droplets are broken into smaller droplets during the low interfacial tension state that occurs during phase transition, induced by the water dilution. In the phase inversion temperature (PIT) method, the phase inversion occurs by cooling the mixture. W/O nanoemulsions can be prepared by employing the same methodology.