title: Surface-active properties of the antitumour ether lipid 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (edelfosine).
abstract: The surface activity and interaction with lipid monolayers and bilayers of the antitumour ether lipid 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (edelfosine) have been studied. Edelfosine is a surface-active soluble amphiphile, with critical micellar concentrations at 3.5 microM and 19 microM in water. When the air-water interface is occupied by a phospholipid, edelfosine becomes inserted in the phospholipid monolayer, increasing surface pressure. This increase is dose-dependent, and reaches a plateau at ca. 2 microM edelfosine bulk concentration. The ether lipid can become inserted in phospholipid monolayers with initial surface pressures of up to 33 mN/m, which ensures its capacity to become inserted into cell membranes. Upon interaction with phospholipid vesicles, edelfosine exhibits a weak detergent activity, causing release of vesicle contents to a low extent (<5%), and a small proportion of lipid solubilization. The weak detergent properties of edelfosine can be related to its very low critical micellar concentrations. Its high affinity for lipid monolayers combined with low lytic properties support the use of edelfosine as a clinical drug. The surface-active properties of edelfosine are similar to those of other "single-chain" lipids, e.g. lysophosphatidylcholine, palmitoylcarnitine, or N-acetylsphingosine.
authors.affiliation: Unidad de Biofísica (Centro Mixto CSIC-UPV/EHU), and Departamento de Bioquímica, Universidad del País Vasco, PO Box 644, 48080 Bilbao, Spain.
authors.forename: Jon V
authors.initials: JV
authors.lastname: Busto
authors.forename: Jesús
authors.initials: J
authors.lastname: Sot
authors.forename: Félix M
authors.initials: FM
authors.lastname: Goñi
authors.forename: Faustino
authors.initials: F
authors.lastname: Mollinedo
authors.forename: Alicia
authors.initials: A
authors.lastname: Alonso
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D008051:Lipid Bilayers / Q000737:chemistry; D008823:Micelles; D010742:Phospholipid Ethers / Q000737:chemistry*; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D053835:Unilamellar Liposomes / Q000737:chemistry
chemical_list: D000970:Antineoplastic Agents; D008051:Lipid Bilayers; D008823:Micelles; D010742:Phospholipid Ethers; D013501:Surface-Active Agents; D053835:Unilamellar Liposomes; C026659:edelfosine