Biological systems are driven by interactions between biomolecules-DNA, proteins and small molecules. Protein-protein/ligands interactions are involved in virtually all cellular processes including metabolism, signaling and development. Considering that body fluids such as blood, intracellular liquid and saliva etc. are protein solutions where these molecules perform their physiological functions; knowledge of their molecular structures in solution is highly relevant. This Chapter summarizes the work that has been done in this field during the course of my PhD tenure and highlights some future work. The last Chapters focused on some of the different phase states of biopolymer solutions that can exist in equilibrium at room temperature. Dispersions, followed by complex coacervation and gelation phases were systems were studied in IL solutions. IL is quite different from inorganic salts due to its delicate balance between the ionic and hydrophobic composition.