Whole-cell imaging at nanometer resolutions using fast and slow focused helium ions

Area of Science:

• Cell Biology
• Microscopy
• Biophysics

Background:

• Understanding organelle function requires detailed observation of cellular interior structures.
• Existing microscopy techniques face limitations in achieving high resolution for both cell surfaces and interiors simultaneously.

Purpose of the Study:

• To explore the application of helium ion microscopy for high-resolution imaging of cell surfaces and internal structures.
• To demonstrate the capability of both slow and fast helium ions for distinct imaging applications within cell biology.

Main Methods:

• Utilized slow (keV) helium ion beams focused to subnanometer dimensions for high-resolution cell surface imaging.
• Employed fast (MeV) helium ions to penetrate cells, measuring energy loss to construct mass distribution images.
• Leveraged electron beams for sample charge neutralization, eliminating the need for metallic coatings on cell surfaces.

Main Results:

• Achieved subnanometer resolution on cell surfaces using slow helium ion microscopy without conductive coating.
• Developed energy-loss imaging with fast helium ions to represent cellular mass distribution at nanometer resolution.
• Demonstrated the potential for structural, elemental, and fluorescence imaging using helium ions.

Conclusions:

• Helium ion microscopy provides a versatile platform for comprehensive whole-cell investigations at nanometer resolution.
• The dual capability of slow and fast helium ions enables detailed surface and internal cellular analysis.
• This technology advances the study of organelle function and cellular structure.