(405b) Phase Diagram Visualization Via Continuously-Fed Crystallization: Experiments and Model

X-ray diffraction is the most common way to determine structural information of proteins at an atomic level. Elucidation of these structures has a dynamic impact on biotechnology and pharmacology. To determine the protein structure, a high-quality crystal of sufficient size is required. However, the production of such crystals is a current bottleneck. Current technology involves hundreds of conditions in this multi-parametric process to be tested by either batch or vapor diffusion crystallization techniques. Knowledge of the phase diagram allows experimenters to better design experiments to grow large high quality crystals.

A continuous-feed crystallization chamber is manufactured to allow phase diagram visualization to predict the phase diagram of a protein in a single experiment. This microfluidic system allows the experimenter to screen a large range of salt and protein concentrations by controlling the convection and diffusion of both protein and salt. A continuous-feed crystallization chamber has been successfully fabricated and characterized in terms of its flow profile. The protein and salt concentration profiles are determined using a computational model. Experimental results determine locations where crystals form and in combination allow determination of the phase diagram. This device has successfully predicted the well-known phase diagram for tetragonal lysozyme and has been utilized on triclinic lysozyme, a protein crystal for which the full phase diagram is unknown.