Abstract: Nanoemulsions are prepared containing oily droplets of a diameter of less than 100 nm in an aqueous phase. The oily droplets contain a lipophilic substance, and have on their surface an amphoteric emulsifier in an amount of preferably 0.65 to 0.75 parts by weight amphoteric emulsifier for one part by weight of oily component forming the droplets. The oily component of the droplets is preferably a triglyceride containing oleic acid and/or linoleic acid. The nanoemulsions, which may be sterile, are used for delivering into cells the lipophilic substance contained by the oily droplets. This delivery can be used to biotransform the lipophilic substance, promote cell differentiation, growth or biosynthesis of a desired substance, or to test for toxicity of the lipophilic substance.

Abstract: Nanoemulsions are used for completion of cell cultures with lipophilic substances promoting the biosynthesis of desired substances within the cells; as well as for the defined and reproducible uptake of lipophilic substances into the cells of cell cultures. Preferred nanoemulsions have oily particles of a diameter of less than 100 nm, the surface of which is bearing a monolayer of an amphoteric emulsifier, which oily particles comprise a lipophilic substance to be tested in or to be delivered to a cell culture, said oily particles, said lipophilic substances dissolved therein and the aqueous phase being sterile.

Abstract: Sterile nanoemulsions are prepared containing oily droplets of a diameter of less than 100 nm in an aqueous phase. The oily droplets contain a lipophilic substance, and have on their surface an amphoteric emulsifier in an amount of preferably 0.65 to 0.75 parts by weight amphoteric emulsifier for one part by weight of oily component forming the droplets. The oily component of the droplets is preferably a triglyceride containing oleic acid and/or linoleic acid. The nanoemulsions are used for delivering into cells the lipophilic substance contained by the oily droplets. This delivery can be used to biotransform the lipophilic substance, promote cell differentiation, growth or biosynthesis of a desired substance, or to test for toxicity of the lipophilic substance.