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 2-ELECTRON CARRIER

Photostimulated vectorial electron transfer through the lecithin bilay er membrane was studied in a system based on lipid vesicles with CdS a s a photosensitizer located either in the vesicle inner cavity or outs ide the vesicles. 1,4-Bis(1,2,6-triphenyl-4-pyridyl) benzene (benzovio logen) was used as an effective lipophilic highly reversible electron carrier incorporated into the bilayer membrane. A peculiarity of this electron carrier is its ability to be reversibly reduced on one and tw o electrons. The interface electron transfer across the border ''vesic ular cavity-membrane'' was studied by stationary and pulse photolysis. The primary photoreduced form of benzoviologen appears to be that red uced by one electron; however, on stationary photolysis, most benzovio logen molecules appear to be affected by two-electron reduction, which can result from the low mutual mobility of CdS nanoparticles and benz oviologen molecules. The CdS photostimulated transmembrane electron tr ansfer from the internal sacrificial donor to the external acceptor (a s regards the vesicular cavity) was performed for [CoEDTA](-) as the f inal electron acceptor. The rate constants of electron transfer from t he membrane-embedded two-electron reduced form of benzoviologen have b een determined in the case of [CoEDTA](-) and O-2 as accepters.