solution is stable [@Lu1994].

![Schematic representations of different proteins adsorbed on the surface. (a) Alb (smaller) and IgG (larger) are approximated as globular proteins with radiuses $R_A<R_I$. In all the panels the continuous line represents the surface profile. (b) Fib is represented as an ellipsoid with a short axis $R_F$ and a long axis $\delta_F$. Fib can assume different conformations: “lying down”, as in (b), or “standing up”, as in (c), possibly giving rise to mixed configurations, as in (d).[]{data-label="Fig1"}](Fig1)

The Fib in its folded conformation is rod-like. We approximate it with an elongated ellipsoid, with two principal axes of rotation, that can assume two different conformations, one “lying down” and another “standing up” on the surface (Fig. \[Fig1\]). This idea is consistent with experiments [@Roach2005] and has been used in Monte Carlo simulations with potentials within the DLVO theory [@Bellion2008]. Here the two different conformations are encoded in an effective way through soft-core Fib-“protein $i$” potentials, $$V_{F,i}(r)\equiv\epsilon_{F,i}\left[\left(\frac{\sigma_{F,i}}{r}\right)^{24}+\frac{3}{1+\exp\left(30\left(r-\delta_{F,i}\right)/\sigma_{A}\right)} \right]
\label{2}$$ where $i=A, I, F$ stands for Alb, IgG and Fib, with $\sigma_{F,i}\equiv R_F+R_i$ corresponding to the interaction along the short axis, $\delta_{F,i}\equiv\delta_F+\delta_i$ corresponding to the interaction along the long axis, $\delta_A\equiv R_A$, $\delta_I\equiv R_I$, $\delta_F$ the long axis of Fib, 