Vectorial phototransfer of electrons across lipid membranes

Abstract

Vectorial electron phototransfer across lipid membranes assisted by molecules - carriers of electrons can be used for providing spatially separated strong oxidant and reductant species• In this work the kinetics and mechanisms of the transmembrane vectorial electron phototransfer from donors located in the inner cavities of the lecithin lipid vesicles to acceptors located outside the vesicles were studied in two systems. The EDTA-ZnTPP-Methylviologen system contains tetraphenylporphyrinatozinc embedded into vesicular membrane. ZnTPP serves both as a photosensitizer and as a carrier of electron from EDTA to methylviologen. The Ru(bipy)2-Cetylvio-logen-Fe(CN)§ system contains an electron carrier - cetylvio-logen, embedded into the membrane. Under light the viologen transfers electron from photosensitizer - Ru(bipy)3+ located in the inner cavity of the vesicle through membrane to Pe(CN)3-in the bulk volume. The possibilities are discussed of using photochemical systems based on lipid vesicles for accomplishing water cleavage. © 1988 IUPAC