Spectrophotometric investigation of the binding of vitamin E to water-containing reversed micelles
- Autori: Avellone, G.; Bongiorno, D.; Ceraulo, L.; Ferrugia, M.; TURCO LIVERI, V.
- Anno di pubblicazione: 2002
- Tipologia: Articolo in rivista (Articolo in rivista)
- Parole Chiave: Membrane models; Reversed micelles; UV-vis spectroscopy; Vitamin E; 3003
- OA Link: http://hdl.handle.net/10447/243654
The distribution constants of vitamin E partitioned between apolar organic phase and water-containing reversed micelles of sodium bis (2-ethylhexyl) sulfosuccinate (AOT), didodecyldimethylammonium bromide (DDAB), soybean phosphatidylcholine (lecithin) and tetraethylene glycol monododecyl ether (C12E4) have been evaluated by a spectrophotometric method. The results suggest that in the presence of domains from apolar organic solvent to surfactant and to water, vitamin E is partitioned between the micellar palisade layer and the organic solvent and also that its binding strength to reversed micelles depends mainly by specific interactions between the head group of vitamin E and that of the surfactant. Moreover, in addition to the advantageous interactions between vitamin E and water, the dependence of the distribution constants upon the molar ratio R (R=[water]/[surfactant]) indicates a competition between water and vitamin E for the binding sites at the water/surfactant interface. The biological implications of the preferential location and confinement of vitamin E in water-containing reversed micelles are discussed. Â© 2002 Elsevier Science B.V. All rights reserved.