Photostimulated vectorial electron transfer across the bilayer membrane of lipid vesicles in a system with CdS nanoparticles as photosensitizer and 1,4--bis(1,2,6-triphenyl-4-pyridyl)benzene as a reversible two-electron carrier

✍ Scribed by T.I. Igumenova; V.N. Parmon

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 700 KB
• Volume: 90
• Category: Article
• ISSN: 1010-6030
• DOI: 10.1016/1010-6030(95)04085-t

✦ Synopsis

Photostimulated vectorial electron transfer through the lecithin bilayer membrane was studied in a system based on lipid vesicles with CdS as a photosensitizer located either in the vesicle inner cavity or outside the vesicles. 1,4-Bis (1,2,6-triphenyl-4-pyridyl) benzene (benzoviologen) was used as an effective lipophilic highly reversible electron carder incorporated into the bilayer membrane. A peculiarity of this electron carrier is its ability to be reversibly reduced on one and two electrons. The interface electron transfer across the border "vesicular cavity-membrane" was studied by stationary and pulse photolysis. The primary photoreduced form of benzoviologen appears to be that reduced by one electron; however, on stationary photolysis, most benzoviologen molecules appear to be affected by two-electron reduction, which can result from the low mutual mobility of CdS nanoparticles and benzoviologen molecules. The CdS photostimulated transmembrane electron transfer from the internal sacrificial donor to the external acceptor (as regards the vesicular cavity) was performed for [ CoEDTA]as the final electron acceptor. The rate constants of electron transfer from the membrane-embedded two-electron reduced form ofbenzoviologen have been determined in the case of [CoEDTA] -and 02 as acceptors.