Support

The Injector Group will continue development of the solvated sample injectors. This includes not only the current Gas-Dynamic Virtual Nozzles (GDVN), but also new and different designs for transporting biological samples from bulk solution into the XFEL beam (focal spot 0.1 to 1 micron diameter) in the vacuum of the FEL sample chamber. Notable among these new varieties is the Lipidic Cubic Phase LCP) extrusion injector that is being developed primarily by Uwe Weierstal.

The major goals of the injector development are (1) reducing sample consumption, (2) improving nozzle and jet properties (straighter, smaller, and more stable jets), and (3) developing mass production techniques for nozzle fabrication. Towards the first end, they are developing a pulsed version of the GDVN (“spurted” would perhaps be a better description) that promises a reduction of 100 or more in sample consumption and thereby gets them down into the 100nl/min range that is considered useful for precious biological samples. The LCP jet already runs at this very low flow rate but could use improvements in stream stability and diameter. Towards the second and third goals, the Doak Group is actively designing nozzle structures that potentially can be fabricated to very high spatial resolution and symmetry by means of two-photon laser lithography.