Phase stability of colloidal mixtures of spheres and rods

We determined the phase boundaries of aqueous mixtures containing colloidal rod-like fd-viruses and polystyrene spheres using diffusing-wave spectroscopy compared results with free volume theory predictions. Excluded interactions in rods lead to mediated depletion interactions. The strength range this attractive interaction depend on concentrations particles, length L diameter D rods, radius R spheres. At strong enough attraction, leads separation. experimentally rod sphere where these transitions occur by systematically varying size ratios L/R D/R aspect ratio L/D. This was done different radii modifying effective through either ionic buffer or anchoring a polymeric brush surface rods. observed were from binary fluid gas/liquid coexistence that occurred already at very low due efficiency highly anisotropic measured obtained (FVT), well established for calculating behavior particles mixed depletants. find good correspondence between experimental theoretical FVT model excluded depletants explicitly accounted both reservoir system.