Novel microfluidic technologies: toward a low-cost system for protein crystallization.

Abstract

The three-dimensional structure of folded proteins is of enormous interest to the scientific community. The structure is best determined with x-ray diffraction through a protein crystal, but it has proven extremely difficult to grow crystals large enough for this process [1, 2]. Significant challenges faced by protein crystallographers include the inability to sufficiently control the crystallization environment and the scarcity of protein available [3]. Microfluidic devices, which allow ultra-precise fluid management and require significantly less reagent than traditional methods, constitute an ideal technology with which to overcome these crystallization challenges [4-7]. A microfluidic system has been designed to give a crystallographer precise management of the concentrations of several reagents (such as protein and a suitable precipitant salt) over time. To create components of the microfluidic system, two novel fabrication methods were developed: photopolymer mold making and three-dimensional plate tectonics. These methods are rapid, inexpensive, and do not require any special equipment. A novel micropump and channel network suitable for the crystallization system were successfully created using these techniques.