High average brightness water window source for short-exposure cryomicroscopy.

Area of Science:

• Biophysics
• X-ray microscopy
• Laser plasma physics

Background:

• Laboratory water window cryomicroscopy offers image quality comparable to synchrotron-based methods.
• Current limitations include prolonged exposure times, hindering broader scientific adoption.
• Advancements are needed to make this technique more accessible.

Purpose of the Study:

• To demonstrate high-resolution laboratory water window imaging of cryofrozen cells.
• To achieve significantly reduced exposure times compared to previous methods.
• To establish the feasibility of advanced X-ray microscopy outside of synchrotron facilities.

Main Methods:

• Utilized a novel laser plasma source operating at a wavelength of 2.48 nm with a 2 kHz repetition rate.
• Employed a liquid nitrogen jet for stable plasma generation.
• Achieved high spatial and temporal stability with high average brightness (>1.5×10^12 ph/(s×sr×μm^2×line)).

Main Results:

• Successfully performed high-resolution imaging of cryofrozen cells within a 10-second exposure time range.
• Demonstrated image quality comparable to synchrotron-based microscopy.
• The laser plasma source exhibited high stability and brightness, approaching early synchrotron capabilities.

Conclusions:

• The developed laboratory water window X-ray microscopy system significantly reduces exposure times.
• This advancement enables biological X-ray microscopy in a home laboratory setting.
• The high-brightness, stable laser plasma source opens possibilities for applications previously exclusive to synchrotrons.