PHOTOCONDUCTIVITY IN BLACK LIPID AND THIN LIPID MEMBRANES

TIEN has recently reported1,2 that black or bilayer lipid membranes and thin lipid membranes containing photo-synthetic pigments such as chlorophylls and xanthophylls possess photoconductive properties. He illuminated one side of the membrane from a source of fixed intensity and observed the changes in current flowing through, and in potential across, the membrane on illumination. The source was a 500 W tungsten lamp with a lens and heat filter, but the extent to which radiation heating of the membrane was reduced by the filter is uncertain. The thermal contribution in the reported photo effects is therefore also uncertain. © 1969 Nature Publishing Group.