Overview
Several techniques are available to successfully deliver your crystalline sample into the X-ray interaction point in a serial fashion.
The importance of successful sample delivery
In order to measure X-ray diffraction from crystals using the serial femtosecond crystallography method, we need to replenish the sample in the X-ray interaction point after each X-ray pulse. A stable sample delivery method is therefore critical for any LCLS experiment.
Next, to replenish the crystalline sample before the next X-ray pulse arrives, the sample delivery method should:
- Not cause any damage to the sample
- Be compatible with running in vacuum, helium, or air
- Minimize the background scattering from the carrier medium (for example, water molecules or the lipidic cubic phase)
- Operate reliably for hours
Sample delivery methods available at LCLS
A wide array of sample delivery methods is available for experiments at LCLS, each with its own advantages and disadvantages. Although an overview is given below, feel free to reach out to your point of contact for advice.
Pros | Cons | Ideal For |
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Gas Dynamic Virtual Nozzle(GDVN) |
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GDVN plus mixer |
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Double Flow Focusing Nozzles (DFFN) |
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Rayleigh Jets |
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High Viscosity Extruders |
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Microfluidic Electrokinetic Sample Holder (MESH) |
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Concentratic Mesh (CoMesh) |
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Droplet Injectors |
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Fixed Targets |
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Lens Stack |
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In addition, there are some methods not owned by SLAC that have been used at LCLS in the past and may be available through collaboration.
- Acoustic levitation
- Rowed runner
- Tape drive
Preparing for a serial crystallography experiment
We can advise LCLS users on which injection method is best suited for your project. In addition, we offer tools for extensive testing and characterization of the chosen sample delivery method before your beamtime takes place. For more information, please have a look at the laboratories we have available for our users.