Fabrication of supported lipid bilayers of designed shape with micro-printing and replica-molding

Membrane curvature is a fundamental part of the cellular machinery. In cells, membrane curvature can be generated by different mechanisms, including cytoskeletal scaffolding and lipid and protein sorting. In protein-free systems in vitro, membrane curvature can be artificially obtained by, for example, membrane micro-manipulation, phase separation, and supported lipid bilayers fabrication. However, until now, these methods allowed for studying a restricted range of shapes only. Here, we present a general and facile method to obtain membranes of designed curvature with high precision. By combining 3D micro-printing and replica-molding lithography, we fabricate scaffolds of designed shape and size suitable for lipid coating. We show that the resulting supported lipid bilayers are homogeneous and fluid. We demonstrate their potential by using them for fluorescence after photobleaching and phase separation experiments on curved surfaces. We anticipate that our method will open new possibilities to investigate curvature sensing proteins and, more generally, the role of membrane curvature in biology.