Crystal Nucleation Rates for Particles Experiencing Short-Range Attractions: Applications to Proteins

Abstract

A kinetic model for the nucleation of a crystalline phase consisting of particles experiencing short-range attractions is developed. Of particular significance is the proximity of the metastable fluid/fluid phase boundary. The model incorporates self-consistent thermodynamics, changes in gradient diffusivity, and density fluctuations in the vicinity of the critical point. Density fluctuations associated with the spinodal of this metastable phase transition greatly enhance nucleation rates, suggesting that experimental conditions may be found where rapid nucleation and slow crystal growth can be achieved by moving the metastable critical point relative to the solubility boundary.