Oil adjuvants are also called emulsion adjuvants (either oil-in-water or water-in-oil). Oil adjuvants were first reported at 1916 by Le moinic and Pinoy. Jules Freund developed a vaccine adjuvant which was a mineral oil-based water-in-oil emulsion called Freund’s adjuvant to enhance this concept. The Freund’s adjuvant is one of the most commonly used adjuvants in vaccine research and is used for the initial injections as a water-in-oil emulsion. Because of the noticeable effects of emulsions as carriers of vaccine protein and of immune-stimulatory molecules, they have a wide and diverse potential in vaccine development.
https://www.creative-biolabs.com/vaccine/oil-adjuvant.htm
