Experimental determination of water equilibration rates in the hanging drop method of protein crystallization

The hanging drop method for protein crystallization consists of equilibrating a water droplet containing the protein and a precipitant against a reservoir solution at a higher precipitant concentration. The time for water equilibration—which affects the kinetics of crystallization—to reach 90% of completion is shown to vary between about 25 h and more than 25 days, depending on experimental conditions. Experiments were performed with three of...