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The presence of ethanol can lead to the formations of non-lamellar phases also known as non-bilayer phases. Ethanol has been recognized as being an excellent solvent in an aqueous solution for inducing non-lamellar phases in phospholipids. The formation of non-lamellar phases in phospholipids is not completely understood, but it is significant that this amphiphilic molecule is capable of doing so. The formation of non-lamellar phases is significant in biomedical studies which include drug delivery, the transport of polar and non-polar ions using solvents capable of penetrating the biomembrane, increasing the elasticity of the biomembrane when it is being disrupted by unwanted substances (viruses, bacteria, solvents, etc.) and functioning as a channel or transporter of biomaterial. == Biomembranes and phospholipid bilayers == Biological membranes are found in both prokaryotic and eukaryotic cells.〔Yeagle, Philip. ''The Membrane of Cells''. 2nd ed. Academic Press, 1993. 1–7〕 They surround cells and organelles with a semi-permeable barrier that prevents free flow of substances. The membrane consists of a phospholipid bilayer structure and often embedded or otherwise associated proteins, along with cholesterol and glycolipids.〔Lodish, Harvey; Berk, Arnold; Matsudaira, Paul; Berk, Arnold; Matsudaira, Paul; Kaiser, Chris A.; Krieger, Monty; Scott, Matthew P.; Zipursky, S. Lawrence; Darnell, James. ''Molecular Cell Biology''. 5th ed. W.H. Freeman and Company New York, 2004. 535–539.〕 The phospholipid bilayer is a two-layer structure mainly composed of phospholipids, which are amphiphilic molecules that have hydrophilic and hydrophobic regions.〔 The hydrophilic region contains the polar head group. This region is exposed to aqueous substances located mainly in the exterior portion of the biomembrane. The hydrophilic region consists of the non-polar acyl chains or fatty acids groups facing the interior of the biomembrane. Phospholipids consist of two non-polar hydrocarbon chains with ester or ether bonds to the phosphate group which is also linked by ester or ether bonds to the polar hydrophilic region.〔 The phospholipid carries a negative charge due to the presence of the phosphate group. Its overall polarity depends on the charges of the hydroxyl groups or alcohols such as choline, ethanolamine, inositol, serine, etc. attached to the phosphate group.〔〔 There are six basic functions that are associated with biomembranes:〔〔 #Controlling chemical potential and gradient for chemical species and charges across opposite sides of the membrane #Organizing enzymes and protein complexes for signal transduction or signaling #Managing protein and lipid interactions #Functioning as a substrate #Transferring vital information and material across the membrane #Compartmentalization by maintaining physical separation amongst membranes but still allowing proper communication 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ethanol-induced non-lamellar phases in phospholipids」の詳細全文を読む スポンサード リンク
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