Insolubility of lipids in triton X-100: physical origin and relationship to sphingolipid/cholesterol membrane domains (rafts)

Biochim Biophys Acta. 2000 Nov 23;1508(1-2):182-95. doi: 10.1016/s0304-4157(00)00007-1.


The insolubility of lipids in detergents is a useful method for probing the structure of biological membranes. Insolubility in detergents like Triton X-100 is observed in lipid bilayers that exist in physical states in which lipid packing is tight. The Triton X-100-insoluble lipid fraction obtained after detergent extraction of eukaryotic cells is composed of detergent-insoluble membranes rich in sphingolipids and cholesterol. These insoluble membranes appear to arise from sphingolipid- and cholesterol-rich membrane domains (rafts) in the tightly packed liquid ordered state. Because the degree of lipid insolubility depends on the stability of lipid-lipid interactions relative to lipid-detergent interactions, the quantitative relationship between rafts and detergent-insoluble membranes is complex, and can depend on lipid composition, detergent and temperature. Nevertheless, when used conservatively detergent insolubility is an invaluable tool for studying cellular rafts and characterizing their composition.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Cell Membrane / chemistry*
  • Cholesterol / chemistry
  • Crystallization
  • Fats / chemistry
  • Gels
  • Kinetics
  • Lipid Bilayers / chemistry
  • Lipids / chemistry*
  • Models, Molecular
  • Octoxynol / chemistry*
  • Solubility
  • Sphingolipids / chemistry
  • Temperature


  • Fats
  • Gels
  • Lipid Bilayers
  • Lipids
  • Sphingolipids
  • Octoxynol
  • Cholesterol