Selecting optimal support grids for super-resolution cryogenic correlated light and electron microscopy.

Area of Science:

• Correlated cryo-electron microscopy and super-resolution fluorescence microscopy
• Biological sample imaging techniques
• Nanoscale structural analysis

Background:

• Cryogenic transmission electron microscopy (cryo-TEM) and super-resolution fluorescence microscopy (SRFM) are advanced imaging methods for biological samples.
• Correlated workflows combining cryo-TEM and SRFM offer enriched contextual information but face challenges with light-induced sample damage.

Purpose of the Study:

• To investigate light-induced sample damage during SRFM in correlated cryo-microscopy workflows.
• To identify how TEM support grid design influences light absorption and subsequent sample damage.
• To optimize grid parameters for enhanced SRFM illumination power and image quality in correlated studies.

Main Methods:

• Systematic analysis of TEM support grid geometry and material properties.
• Measurement of light absorption by different grid designs.
• Evaluation of maximum illumination power density achievable in SRFM.
• Assessment of super-resolution image quality post-SRFM illumination on optimized grids.

Main Results:

• Absorption of light by TEM support grids is a primary cause of sample damage during SRFM.
• Modifications in grid geometry and materials can increase maximum illumination power density by up to tenfold.
• Optimized support grids significantly improve super-resolution image quality in correlated cryo-microscopy.

Conclusions:

• TEM support grid selection is critical for mitigating light-induced damage in correlated cryo-microscopy.
• Tailoring grid design offers a pathway to enhance SRFM illumination power and preserve sample integrity.
• Optimized grids enable higher quality super-resolution imaging, enriching cryo-TEM data.