New developments of the IMPAX small-volume automated crystallization system.

Recent developments of the IMPAX system for automated crystallization are presented. A five-channel microtip has been introduced into the system thereby providing an extra degree of freedom for carrying out experiments. A new mouse-driven program for screening has been introduced, which creates a much wider scope for designing and executing screens covering new conditions of crystallization. The hardware has been adapted so that the system can also be used to set up vapour-diffusion trials. A simple design of a vapour-diffusion vessel, suitable for sitting drops of 2-15 microl, using smaller reservoir volumes (up to 100 microl), facilitates large-scale systematic trials.