Two kinds of biomimetic membranes labelled with chlorophyll a and chlorophyllide a were obtained through hydration of a phosphatidylcholine thin film. These artificial membranes were subjected to UVC irradiation (253.7 nm) for different times and were characterized by spectral methods (Vis absorption and emission spectroscopy, Dynamic Light Scattering). The stability of the samples was checked by zeta potential measurements. A photo-bleaching effect occurred depending on the exposure time. The two types of membranes exhibited different photoresponses. Both bioporphyrins proved to be excellent sensors for detection of changes occurred in artificial lipid bilayers, at molecular level.