The Amphipathic reference article from the English Wikipedia on 24-Apr-2004
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Amphipathic

Helping orphans the way you would do it
An amphipathic (a.k.a. amphiphilic) molecule contains both hydrophobic and hydrophilic groups. The hydrophobic group can be a long carbon chain, with the form: CH3(CH2)n, with 4 < n < 16. The hydrophilic group falls into one of the following categories:
  1. Ionic Molecules
    • Anionic (with respect to the charge on the group maintaining hydrophobia). Examples are:
      • fatty acids: RCO2-Na+;
      • sulfates: RSO4-Na+;
      • sulfonates: RSO3-Na+.
    • Cationic. These are generically bactericidal and hence non-biodegradable.
  2. Amphoteric Molecules. Examples are phospholipids, one of the main constituents of biological membranes: they insulate the cells from the surrounding medium.
  3. Non-Ionic Molecules. A small polymer is grafted onto a hydrophobic segment.
  4. Block Copolymers
  5. Floation Additives

See also: Free surface energy, Sodium dodecyl sulfate;