Three-dimensional-printed gas dynamic virtual nozzles for x-ray laser sample delivery

Abstract

Reliable sample delivery is essential to biological imaging using X-ray Free Electron Lasers (XFELs). Continuous injection using the Gas Dynamic Virtual Nozzle (GDVN) has proven valuable, particularly for time-resolved studies. However, many important aspects of GDVN functionality have yet to be thoroughly understood and/or refined due to fabrication limitations. We report the application of 2-photon polymerization as a form of high-resolution 3D printing to fabricate high-fidelity GDVNs with submicron resolution. This technique allows rapid prototyping of a wide range of different types of nozzles from standard CAD drawings and optimization of crucial dimensions for optimal performance. Three nozzles were tested with pure water to determine general nozzle performance and reproducibility, with nearly reproducible off-axis jetting being the result. X-ray tomography and index matching were successfully used to evaluate the interior nozzle structures and identify the cause of off-axis jetting. Subsequent refinements to fabrication resulted in straight jetting. A performance test of printed nozzles at an XFEL provided high quality femtosecond diffraction patterns.

Direct Laser Writing of Low‐Density Interdigitated Foams for Plasma Drive Shaping

“…DLW‐TPP has been used for a variety of applications requiring large volume (millimeter scale) structures with intricate features, including metamaterials for both shock absorption and feel‐ability cloaking, lenses, liquid delivery nozzles, microfluidics, medical devices, as well as bioscaffolds, to support various tissue cultures such as bone stem cells, cartiledge, and dermal cells . While many of the applications above utilized high‐accuracy translation stages for printing parts, the low‐density foams targeted in this work were prepared using a repetitive two‐step sequence of galvoscanning followed by piezo or linear stage‐movements, a process commonly referred to as stitching.…”

“…Galvo scanners offer printing speeds >10 mm s −1 while maintaining high accuracies, which is of critical importance for the fabrication of nanostructured materials. The process of stitching, however, can lead to structural defects and other nonuniformities, especially in porous materials, vide infra. The quality of an individual stitch is dependent on the quality of the motion stage, for which factors such as range of motion, speed, positional accuracy, and cost are to be weighed.…”

Microfluidics: From crystallization to serial time-resolved crystallography

“…More recently, soft lithographic and 3D printing methods for the robust manufacture of nozzles have been reported. 157,158 For all these various GDVN designs, the pressure of the flowing sheath gas is used to focus the liquid stream into a narrower jet that could be achieved by the features of the nozzle alone. This gas-driven focusing also allows for the use of larger capillaries or injector features, relative to the size of the crystals, to decrease the potential for clogging and allow for the modulation of the jet size, relative to the crystal size.…”

Analysis of XFEL serial diffraction data from individual crystalline fibrils

“…Such crystals are easier to obtain than those of at least tens of micrometres across that are required by synchrotron sources. Crystals are usually injected into the XFEL pulse path through a nozzle as a suspension in a liquid jet Nelson et al, 2016;Oberthuer et al, 2017) oriented perpendicular to the incident X-ray path, although other sample-delivery methods are also in use Chavas et al, 2015;Sierra et al, 2015;Roedig et al, 2016;Martin-Garcia et al, 2016;Fuller et al, 2017). The maximum pulse repetition rate at the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory is 120 Hz, and diffraction patterns are usually recorded at this rate (Bostedt et al, 2016).…”