Our research focuses on studying the physical chemistry governing various methods of membrane protein crystallization. Membrane proteins are critical components of many fundamental biological processes such as ion regulation and transport through the cell membrane and catalyzing reactions such as charge separation and conversion of energy. Membrane proteins also serve as a channel for signal transduction from one side of the cell membrane to the other and establish contact with the proteins of neighboring cells to form tissues such as muscles. Our understanding of such fundamental membrane-associated biological processes at a molecular level is limited due to the lack of knowledge of high-resolution structure of the membrane proteins which depend on obtaining X-ray quality crystals of proteins. While traditional well plate technology is well established, such systems typically use large and expensive fluid handling equipment, and may be on a scale that is inaccessible given the quantities of protein available. The goal of this work is to gain a deeper understanding of the phase behavior of the solutions/gels used for membrane protein crystallization. This study intends to address the challenge of membrane protein crystal growth by the development and validation of novel crystallization platforms. In this presentation we present a novel microfluidic platform that enables the rapid identification and optimization of crystallization conditions for membrane proteins and other molecules by precise control of the evaporation rate. In this manner we can independently control the rate of supersaturation and ensure a phase transition for every trial. The advantage of controlling the rate of supersaturation independently manifests in the improvement of crystal quality and an increase in crystal size in the case of soluble as well as membrane proteins. In addition, the microfluidic platform requires only ~5nL of sample per trial. This technology will help facilitate the crystallization of membrane proteins by easing the sample volume necessary for screening.