Effect of alcohol chain length on tubule formation in 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine.
Aqueous dispersions of 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine, on cooling below the chain melting temperature, form hollow cylindrical structures known as 'tubules'. We have studied the formation of tubules in methanol/water, ethanol/water and n-propanol/water. For each alcohol, there is a defined window of alcohol/water ratios in which the lipid precipitates with the tubule morphology. As the chain length of alcohol is increased, the window shifts towards lower alcohol fraction. Light scattering studies show that at very low lipid concentrations the tubules self-assemble directly from the isotropic phase where as for lipid concentrations greater than 4 mg/ml an intermediate L alpha phase is observed. These results indicate that the mechanism of tubule formation may be dependent on lipid concentration.
Ratna
B R
BR
Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington DC 20375-5320.
Baral-Tosh
S
S
Kahn
B
B
Schnur
J M
JM
Rudolph
A S
AS
D000438:Alcohols / Q000737:chemistry; D053280:Diynes; D008027:Light; D008051:Lipid Bilayers / Q000737:chemistry; D008854:Microscopy, Electron; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D010713:Phosphatidylcholines / Q000737:chemistry*; D012542:Scattering, Radiation; D013696:Temperature; D014867:Water
D000438:Alcohols; D053280:Diynes; D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D014867:Water; C053923:1,2-bis(10,12-tricosadiynoyl)phosphatidylcholine