Compact tape-driven sample delivery system for serial femtosecond crystallography

Area of Science:

• Structural Biology
• Biophysics
• Biochemistry

Background:

• Time-resolved serial femtosecond crystallography (TR-SFX) is crucial for observing rapid molecular dynamics.
• Existing methods for sample delivery and reaction initiation can be complex and limit data collection efficiency.

Purpose of the Study:

• To develop a novel, compact tape drive (CoT) system for on-demand sample delivery in TR-SFX experiments.
• To enable precise control over mixing times and reaction initiation for observing fast biological processes.

Main Methods:

• A compact tape drive (CoT) system was engineered with two piezoelectric injectors for nanolitre droplet delivery.
• X-ray free-electron laser (XFEL) pulses were synchronized and aligned with droplets on the tape.
• Variable tape speed and delivery distance allowed for adjustable mixing times (130 ms to tens of seconds).

Main Results:

• The CoT system demonstrated effective drop-on-drop sample delivery and reaction initiation.
• Time-resolved SFX experiments were successfully conducted using a hen egg white lysozyme (HEWL) and N-acetyl-D-glucosamine (GlcNAc) binding model.
• The complete binding process of GlcNAc to HEWL was observed within a time frame of 1.3-9.7 seconds.

Conclusions:

• The developed CoT system significantly enhances efficiency in TR-SFX data collection.
• This technology provides a versatile platform for studying fast biochemical reactions with high temporal resolution.
• The CoT system facilitates detailed observation of molecular interactions and dynamic processes.