Combined Super-Resolution Fluorescence and Coaxial 3D Scanning Microwave Microscopy: Proof-Of-Concept In-Liquid...

Area of Science:

• Biophysics
• Microscopy
• Nanotechnology

Background:

• Accurate nanoscale imaging of live cells is crucial for understanding biological processes.
• Existing microscopy techniques often lack the ability to simultaneously probe electrical properties at high resolution.
• Near-field scanning microwave microscopy (SMM) offers quantitative local microwave measurements but faces challenges with biological media.

Purpose of the Study:

• To present a proof-of-concept 3D scanning microwave microscope for in-liquid, live-cell imaging.
• To integrate electrical (GHz) and optical (super-resolution) imaging capabilities.
• To establish a foundation for nanoscale imaging across the electromagnetic spectrum.

Main Methods:

• A miniaturized coaxial probe was combined with high-resolution fluorescence microscopy.
• The system operates in-liquid, enabling live-cell imaging.
• A shielded tip design minimizes microwave absorption by biological media.

Main Results:

• Simultaneous electrical and optical imaging of live cells was achieved.
• The system demonstrated micrometric spatial resolution in the 0.01–6 GHz frequency range.
• A shielded probe design significantly improved signal integrity compared to unshielded tips.

Conclusions:

• The developed system provides a novel platform for in-liquid, multi-modal nanoscale imaging.
• This technology lays the groundwork for future nano-radar imaging systems for biological applications.
• Integration with super-resolution microscopy offers a comprehensive approach to probing biology from DC to lightwave.