Polyimide mesh-based sample holder with irregular crystal mounting holes for fixed-target serial crystallography

Area of Science:

• Structural Biology
• Crystallography
• Biophysics

Background:

• Serial crystallography (SX) allows room-temperature structure determination with minimal radiation damage.
• Fixed-target (FT) scanning is an SX method that conserves sample and reduces crystal damage.
• Random crystal orientation on sample holders is crucial for comprehensive 3D data collection.

Purpose of the Study:

• To develop an improved sample holder for FT-SX that promotes random crystal orientation.
• To enhance the efficiency and data quality of FT-SX experiments.

Main Methods:

• Fabrication of a polyimide mesh sample holder using a picosecond laser.
• The laser process created irregularly shaped mounting holes, promoting random crystal settling.
• Sample preparation involved spreading crystals onto the mesh and sealing with polyimide film to prevent dehydration.

Main Results:

• The polyimide mesh holder successfully facilitated random orientation of crystals.
• Fixed-target serial crystallography (FT-SX) was performed using the developed sample holder.
• The room-temperature structure of lysozyme was determined at a resolution of 1.65 Å.

Conclusions:

• The novel polyimide mesh sample holder with irregular holes is effective for FT-SX.
• This sample holder design can improve crystal delivery and expand applications in serial crystallography.
• The technique enables high-resolution room-temperature structure determination with reduced sample damage.