Plug-and-play polymer microfluidic chips for hydrated, room temperature, fixed-target serial crystallography. Issue 24 (25th November 2021)

• Record Type: Journal Article
• Authors: Gilbile, Deepshika; Shelby, Megan L.; Lyubimov, Artem Y.; Wierman, Jennifer L.; Monteiro, Diana C. F.; Cohen, Aina E.; Russi, Silvia; Coleman, Matthew A.; Frank, Matthias; Kuhl, Tonya L.
• Is Part Of: Lab on a chip. Volume 21:Issue 24(2021)
• Page Start: 4831
• Page End: 4845
• Publication Date: 2021-11-25
• Subjects: Miniature electronic equipment -- Periodicals; Combinatorial chemistry -- Periodicals; Biotechnology -- Periodicals; 543.0813
• DOI: 10.1039/d1lc00810b
• Languages: English
• ISSNs: 1473-0197

Abstract

Abstract : This work presents our development of versatile, inexpensive, and robust polymer microfluidic chips for routine and reliable room temperature serial X-ray crystallography measurements. Abstract : The practice of serial X-ray crystallography (SX) depends on efficient, continuous delivery of hydrated protein crystals while minimizing background scattering. Of the two major types of sample delivery devices, fixed-target devices offer several advantages over widely adopted jet injectors, including: lower sample consumption, clog-free delivery, and the ability to control on-chip crystal density to improve hit rates. Here we present our development of versatile, inexpensive, and robust polymer microfluidic chips for routine and reliable room temperature serial measurements at both synchrotrons and X-ray free electron lasers (XFELs). Our design includes highly X-ray-transparent enclosing thin film layers tuned to minimize scatter background, adaptable sample flow layers tuned to match crystal size, and a large sample area compatible with both raster scanning and rotation based serial data collection. The optically transparent chips can be used both for in situ protein crystallization (to eliminate crystal handling) or crystal slurry loading, with prepared samples stable for weeks in a humidified environment and for several hours in ambient conditions. Serial oscillation crystallography, using a multi-crystal rotational data collection approach, at a microfocus synchrotron beamline (SSRL, beamline 12-1) was used to benchmark the performance of the chips. High-resolution structures (1.3–2.7 Å) were collected from five different proteins – hen egg white lysozyme, thaumatin, bovine liver catalase, concanavalin-A (type VI), and SARS-CoV-2 nonstructural protein NSP5. Overall, our modular fabrication approach enables precise control over the cross-section of materials in the X-ray beam path and facilitates chip adaption to different sample and beamline requirements for user-friendly, straightforward diffraction measurements at room temperature.