Two photobioelectrochemical applications of self-assembled films on mercury

The homogeneous, defect-free surface of a hanging mercury drop electrode was used to self-assemble films apt for the investigation of two photobioelectrochemical systems. Monolayers of straight-chain C-12 -C-18 alkane-1-thiols were anchored to a hanging mercury drop electrode and a film of chlorophyll was self-assembled on the top of them. The dependence of the photocurrents generated by illumination of the chlorophyll film with red light, on the thickness of the alkane-1-thiol monolayer and the applied potential is discussed. The photocurrents of purple membrane fragments, adsorbed on a mixed hexadecane-1-thiol/ dioleoylphosphatidylcholine bilayer self-assembled on mercury, were investigated in the presence of sodium perchlorate, chloride and acetate. The effect of the anions on the kinetics of the light-driven proton transport by bacteriorhodopsin has been determined.