Membrane activity detection in cultured cells using phase-sensitive plasmonics.

Area of Science:

• Neuroscience
• Biophysics
• Materials Science

Background:

• Current neural recording techniques face limitations including invasiveness, poor resolution, and signal noise.
• Neuroplasmonics offers a label-free, non-toxic alternative with advantages over traditional methods.
• There is a need for advanced, cost-effective neural recording technologies.

Purpose of the Study:

• To introduce an integrated plasmonic-ellipsometry platform for label-free detection of cellular membrane activity.
• To demonstrate the platform's capability in differentiating neural activity of various cell types.
• To highlight the potential of this technique for high-sensitivity neural signal recording.

Main Methods:

• Utilized cost-effective gratings from commercial DVDs for plasmonic applications.
• Employed ellipsometry to simultaneously measure amplitude and phase of reflected light for enhanced sensitivity.
• Cultured primary hippocampal neurons, SH-SY5Y neuroblastoma cells, and HEK293 cells on the grating surface.
• Applied KCl solution as a chemical stimulus to induce and observe cellular responses.

Main Results:

• Successfully detected membrane activity in cultured cells using the integrated platform.
• Differentiated neural activity between distinct cell types based on optical signals.
• Achieved high signal-to-noise ratio measurements near surface plasmon resonances.
• Demonstrated label-free optical recording of cellular signaling events.

Conclusions:

• The developed plasmonic-ellipsometry platform provides a sensitive, label-free method for neural activity detection.
• This technique overcomes limitations of existing neural recording methods, such as invasiveness and labeling requirements.
• The platform shows significant potential for applications in neuroscience research and diagnostics.