Our measured negative photoconductivity, having a current reduction of ~1 µA that can be translated to a reduction in photocurrent density of ~10 µA•cm -2 , is independent of the excitation wavelengths (Figure ). This finding is very surprising, as the three excitation wavelengths used are in different regions of the UV-Vis absorption of the Chl used in this study (Figure ), showing fundamental different absorption coefficients for these three different wavelengths: 430 nm in the Soret band, 490 nm in a region with very low absorption, and 680 nm in the Q band region. As shown in the studies having the PS as the light-harvesting molecule, the photocurrent magnitude should follow the action spectrum (absorption), meaning that the more photons absorbed, the higher the photocurrent. The fact that we do not see a major change in the photocurrent generation at different wavelengths indicates that our protein matrix is heavily doped, and even when using wavelengths where the doped mat has a low absorption coefficient, we are saturating the photocurrent generation, and that all electronic transitions are resulting in a photocurrent. In an important control experiment, performed with a non-doped BSA mat, we observed a very minor photocurrent only while using the 430 nm blue light (that can be ascribed to a photoelectric effect of the electrodes), and no photocurrent was observed while using a longer wavelength (Figure ). Accordingly, and because of the advantageous use of the long-wavelength low-energy red light, we primarily used it for the rest of the measurements below.