Windowless microfluidic platform based on capillary burst valves for high intensity x-ray measurements

Area of Science:

• Materials Science
• Analytical Chemistry
• Physics

Background:

• High-intensity X-ray measurements require specialized sample delivery systems.
• Existing methods often demand large sample volumes and complex setups.
• Developing efficient microfluidic solutions is crucial for advancing X-ray analysis.

Purpose of the Study:

• To introduce and characterize a microfluidic system for high-intensity X-ray measurements.
• To demonstrate the functionality of an out-of-plane capillary burst valve (CBV) for sample access.
• To assess the system's performance in X-ray scattering experiments.

Main Methods:

• Design and implementation of a microfluidic chip with an out-of-plane capillary burst valve (CBV).
• Characterization of the CBV's performance across various windowless access hole diameters (10-130 microm).
• Testing the microfluidic system at the ESRF synchrotron radiation facility (beamline ID09b).

Main Results:

• The capillary burst valve (CBV) enabled windowless access to the microfluidic channel.
• Demonstrated sample refresh rates from 300 Hz to 54 kHz with pressures from 22 to 280 mbar.
• Successful X-ray scattering measurements were performed with minimal sample consumption (<1 ml/h).

Conclusions:

• The developed microfluidic system is effective for high-intensity X-ray scattering.
• The capillary burst valve (CBV) facilitates efficient sample delivery and high refresh rates.
• The system's design allows for future integration of on-chip mixing and spectroscopy, with potential for wider scattering angles.