Amphiphile (from the Greek αμφις, amphis: both and φιλíα, philia: love, friendship) is a term describing a chemical compound possessing both hydrophilic (water-loving, polar) and lipophilic (fat-loving) properties. Such a compound is called amphiphilic or amphipathic. This forms the basis for a number of areas of research in chemistry and biochemistry, notably that of lipid polymorphism. Organic compounds containing hydrophilic groups at both ends of a prolate (in the aggregate) molecule are called bolaamphiphilic. Common amphiphilic substances are soaps, detergents and lipoproteins.
The lipophilic group is typically a large hydrocarbon moiety, such as a long chain of the form CH3(CH2)n, with n > 4. The hydrophilic group falls into one of the following categories:
Often, amphiphilic species have several lipophilic parts, several hydrophilic parts, or several of both. Proteins and some block copolymers are such examples.
Amphiphilic compounds have lipophilic (typically hydrocarbon) structures and hydrophilic polar functional groups (either ionic or uncharged).
As a result of having both lipophilic and hydrophilic portions, some amphiphilic compounds may dissolve in water and to some extent in non-polar organic solvents.