PHOTOINDUCED PROTON TRANSPORT MECHANISM IN MEROCYANINE-DYE-PROBED PLANAR LIPID-MEMBRANES

Planar lipid membranes were used to study photovoltage generation afte r the incorporation of various merocyanine dyes. These dyes undergo ph otochemical isomerization on illumination and can act as a photon-driv en facilitated proton transport system under suitable conditions. This system has the advantage of preventing back recombination of the phot odissociated charges, thus improving its storage capacity. A sufficien tly high photovoltage, with a long storage time and good reproducibili ty, was obtained with these dyes. The spectral studies indicate the fo rmation of a 1:1 complex between dye and lipid molecules. Our results show that the strength and stability of complex formation increase wit h the hydrophobicity of the dye which, in turn, increase the magnitude and storage of the photovoltage generated in the system.