The human genome contains at least 30,000 unique open reading frames that may yield >100,000 polypeptide products. These products assemble into more than a million biologically relevant structures of interest per organism. In order to obtain a single protein crystal, large amounts of that protein are required to screen for the favorable conditions for crystallization. The 3D structure of proteins needs to be understood for any effective protein engineering, rational drug design, and controlled drug delivery. Moreover, many interesting proteins are unfortunately available in limited supply. A protein crystallization screening platform that consumes only nanoliters of protein solutions will help reduce the consumption of the precious proteins. In addition, small foot print area, complete automation, reduced cost, and the ability to control a large number of parameters on the same platform would be most desirable. All these issues are directly addressed by the recent advances in developing a lab-on-a-chip. In phase I of this project, a disposable lab-on-a-chip will be developed for protein crystallization screening building on our previous demonstrations of electrowetting manipulation of nanoliter-sized water droplets including dispensing, transport, mixing, splitting, and dilution. Phase I work will particularly focus on demonstrating the feasibility of an electrowetting-based lab-on-a-chip for protein crystallization screening. A microfluidic platform will be fabricated for transport and dispensing of nanoliter-sized protein, buffer, & precipitant droplets. The effect of electrowetting will be evaluated on the crystallization of Lysozyme, Chymotrypsin, and GRP 94 under known crystallization conditions. A coarse grid screen will be setup on the integrated lab-on-a-chip platform for demonstrating software programmable set up of screening conditions and crystallization of Lysozyme.
