Spatial Multiplexing of Whispering Gallery Mode Sensors

Area of Science:

• Optics and Photonics
• Biosensing Technologies
• Nanotechnology

Background:

• Whispering gallery mode (WGM) resonators offer sensitive platforms for detecting chemical and biological analytes.
• Current methods struggle with simultaneous multi-channel detection of multiple species.
• Serial addressing of resonators limits throughput and multiplexing capabilities.

Purpose of the Study:

• To develop a novel monitoring scheme for simultaneous multi-channel detection using WGM resonators.
• To overcome the limitations of serial addressing in conventional WGM resonator sensing.
• To enable spatial multiplexing of WGM resonators for parallelized analyte detection.

Main Methods:

• Spatial multiplexing of multiple WGM resonators (microspheres) in an array.
• Simultaneous observation of resonance spectra from individual resonators.
• Utilizing imaging and image processing to monitor glare spot intensities.
• Demonstration with bulk refractive index variations and specific virus-antibody binding events.

Main Results:

• Successfully demonstrated simultaneous recording of resonance spectra from multiple WGM resonators without interference.
• Achieved multiplexed detection, allowing for parallel analysis of different analytes or conditions.
• Validated the approach for both bulk sensing (refractive index changes) and specific biomolecular interactions (virus-antibody binding).

Conclusions:

• The presented spatial multiplexing scheme offers an effective alternative for simultaneous multi-species detection with WGM resonators.
• This approach enhances the capability for high-throughput and multiplexed sensing applications.
• The method provides a robust platform for sensitive trace detection in chemical and biological analysis.