Simple Model of Membrane Proteins Including Solvent
  We report a numerical simulation for the phase diagram of a simple two dimensional model, similar to one proposed by Noro and Frenkel [J. Chem. Phys. \textbf{114}, 2477 (2001)] for membrane proteins, but one that includes the role of the solvent. We first use Gibbs ensemble Monte Caro simulations to determine the phase behavior of particles interacting via a square-well potential in two dimensions for various values of the interaction range. A phenomenological model for the solute-solvent interactions is then studied to understand how the fluid-fluid coexistence curve is modified by solute-solvent interactions. It is shown that such a model can yield systems with liquid-liquid phase separation curves that have both upper and lower critical points, as well as closed loop phase diagrams, as is the case with the corresponding three dimensional model. 
D. L. Pagan, A. Shiryayev, T. P. Connor, and J. D. Gunton