Comparison of VB PES spectra for the three different protein coatings (procedures C, D, and B from left to right from Figure
). The steep straight lines intersecting near 5 eV show the VB position. The sample coated with PC and melanin ( panel b), procedure D in Figure 4) shows 0.6 eV shift on VB position while PC only ( panel a), procedure C in Figure 4) shows 1.0 eV shift under illumination. In the case of αHisPC ( panel c) ), no shift in the VB position is observed.