A simple and versatile microfluidic device for efficient biomacromolecule crystallization and structural analysis by serial crystallography Wijn, Raphaël de Gavira Gallardo, José Antonio Macromolecules Crystallization Counter-diffusion Microfluidics Seeding Determining optimal conditions for the production of well diffracting crystals is a key step in every biocrystallography project. Here, a microfluidic device is described that enables the production of crystals by counter-diffusion and their direct on-chip analysis by serial crystallography at room temperature. Nine ‘nonmodel’ and diverse biomacromolecules, including seven soluble proteins, a membrane protein and an RNA duplex, were crystallized and treated on-chip with a variety of standard techniques including micro-seeding, crystal soaking with ligands and crystal detection by fluorescence. Furthermore, the crystal structures of four proteins and an RNA were determined based on serial data collected on four synchrotron beamlines, demonstrating the general applicability of this multipurpose chip concept 2020-04-23T11:50:34Z 2020-04-23T11:50:34Z 2019 journal article de Wijn, R., Hennig, O., Roche, J., Engilberge, S., Rollet, K., Fernandez-Millan, P., ... & Girard, E. (2019). A simple and versatile microfluidic device for efficient biomacromolecule crystallization and structural analysis by serial crystallography. IUCrJ, 6(3). http://hdl.handle.net/10481/61535 10.1107/S2052252519003622 eng http://creativecommons.org/licenses/by-nc-nd/3.0/es/ open access Atribución-NoComercial-SinDerivadas 3.0 España International Union of Crystallography