In Figure , the modulus data obtained with a probe radius of R = 300 nm showed an overall similar behavior to the prediction of the master curve. When fitting this data directly with Eq. 1, the corresponding fit parameters are A = 0.39 and b = 1.19. As the AFM probe radii decrease, the observed modulus profiles shift further away from the master curve, which indicates the increasing influence of a natural interphase on the normalized modulus coupled with the substrate effect.