Graphene-based microfluidics for serial crystallography.

Area of Science:

• Structural Biology
• Materials Science
• Biophysics

Background:

• Microfluidic platforms are promising for protein crystallography but require reduced device thickness for micro-crystallography.
• Existing methods face challenges in achieving the necessary thinness for on-chip X-ray diffraction.
• Protein targets resistant to traditional single-crystal methods necessitate advanced structural analysis techniques.

Purpose of the Study:

• To develop ultra-thin microfluidic devices for enhanced protein crystallography.
• To integrate single-layer graphene into microfluidic devices to reduce overall thickness.
• To enable on-chip X-ray diffraction analysis of micro-crystals with improved stability.

Main Methods:

• Incorporation of single-layer graphene into microfluidic device fabrication.
• Development of a microfluidic architecture with a total material thickness of approximately 1 μm.
• On-chip X-ray diffraction measurements using polychromatic X-ray exposure.
• Structure determination using hen egg white lysozyme (HEWL) as a model system.

Main Results:

• Achieved ultra-thin microfluidic devices (∼1 μm thickness) using graphene.
• Demonstrated a stable sample environment resistant to water loss for several weeks.
• Obtained excellent signal-to-noise ratios in X-ray diffraction measurements with short exposure times (1.5 μs).
• Successfully performed on-chip structure determination of HEWL.

Conclusions:

• Graphene integration provides a robust strategy for creating ultra-thin microfluidic devices for crystallography.
• The developed platform facilitates on-chip X-ray diffraction and structural studies of challenging protein targets.
• This technology has broad potential applications in X-ray crystallography and other lab-on-a-chip systems.