The inter- and intra-molecular mixing of hydrocarbon chains in lecithin/water systems

✍ Scribed by M.C. Phillips; H. Hauser; F. Paltauf

• Publisher: Elsevier Science
• Year: 1972
• Tongue: English
• Weight: 263 KB
• Volume: 8
• Category: Article
• ISSN: 0009-3084
• DOI: 10.1016/0009-3084(72)90024-2

✦ Synopsis

When pure 1,2 diacyl lecithins containing a different type of hydrocarbon chain in each position of the molecule (intra-molecular chain mixing) are dispersed in excess water, the gel to liquid crystal transition is sharp, as with pure lecithins containing a single type of hydrocarbon chain. The total heat of transition is lower than that observed when the same chain composition is distributed in a mixture of two different lecithins each containing only one type of hydrocarbon chain (inter-molecular mixing). In the latter systems broad transitions are observed, and whenever the experimental temperature is not above that of the transition range clustering of molecules occurs. Bilayers of the isolated lipids of some biological membranes exhibit such clustering at the environmental temperature of the membrane.