Amphiphilia
Amphiphil (noun: amphiphilia) (from ancient Greek ἀμφί amphí “on both sides” and φίλος phílos “loving”), ambiphilic (noun: ambiphilia; mixed word from ambi Latin and phil ancient Greek with the literal meaning “both loving”) and amphipathic describe the chemical Property of a substance that is both hydrophilic and lipophilic . This means that it is readily soluble in both polar solvents and non-polar solvents. This is based on the fact that the molecules have both hydrophilic and hydrophobic areas. The best known polar solvent is water , hence the name hydrophilic. One type of hydrophobicity can be that the substance dissolves well in fats or oils ; it is then called lipophilic . The HLB value is a measure of the amphiphilic properties of a molecule.
Important amphiphilic substances are
- Surfactants used as soaps ; precisely because of the amphiphilia they have the property of having a cleansing effect
- Emulsifiers in food, for example lecithin
- Phospholipids , a major component of cell membranes
- amphipathic helices ; these serve to anchor proteins in a phospholipid membrane
- Nonionic amphiphiles such as B. Polyoxyethanyl α-tocopheryl sebacate (PTS), as solubilizers are used for organic molecules in water and reactions with transition metal - catalysts allow at room temperature.
An important property of amphiphilic substances is the formation of micelles and liposomes (simple form of a biomembrane ).
Individual evidence
- ^ Wilhelm Gemoll: Greek-German school and hand dictionary. Munich / Vienna 1965.
- ↑ amphipathic. In: Wissenschaft-online.de. Retrieved June 5, 2013 .