Microfluidic Platforms for On-chip Formulation and Small-angle X-ray Analysis of the Phase Behavior of Lipid/water Mixtures

We present a microfluidic platform for on-chip formulation and X-ray analysis of lipidic mesophases formed upon mixing lipids and water. The platform is designed to study the effect of detergents on the phase behavior of lipid/water mixtures. The platform allows automated preparation of multiple samples of different composition from stock solutions and subsequent on-chip small-angle X-ray diffraction (SAXS) data collection. To ensure X-ray transparency of the platform we used thin layers of cyclic olefin copolymer (COC) and PDMS. The viability of the platform is demonstrated by mapping out a section of the phase diagram for lipid monoolein mixed with solutions of detergent -octylglucoside.