Are Nucleation Kinetics of Protein Crystals Similar to Those of Liquid Droplets?

We have studied the nucleation of crystals of a model protein from aqueous solutions using a novel technique that allows direct determinations of homogeneous nucleation rates. At a constant temperature of 12.6 °C we varied the thermodynamic supersaturation by changing the concentrations of protein and precipitant. We found a broken dependence of the homogeneous nucleation rate on supersaturation that is beyond the predictions of the classical...