High-sensitivity micro-nano sensor based on q-BIC effect for viral differentiation.

Area of Science:

• Optoelectronics and Photonics
• Biomedical Sensing Technology

Background:

• Surface plasmon resonance (SPR) is a powerful optical phenomenon for detecting refractive index changes.
• Developing highly sensitive and specific sensors for viral infection detection remains a critical challenge in biomedical diagnostics.

Purpose of the Study:

• To propose and demonstrate a novel micro-nano optical sensor based on quasi-bound state in the continuum (q-BIC) and Fano resonance.
• To evaluate the sensor's performance in detecting cells infected with specific viruses.

Main Methods:

• Design and fabrication of a micro-nano optical sensor featuring a rectangular waveguide, baffle, and resonant cavity.
• Excitation of surface plasmon polaritons (SPPs) to achieve SPR via stimulated Fano resonance.
• Structural parameter optimization to enhance sensor performance metrics like sensitivity and Q-factor.
• Experimental validation using cells infected with Herpes Virus type-1, Influenza A, HIV-1, and M13 bacteriophage.

Main Results:

• The optimized sensor achieved a sensitivity of 1133 nm/RIU with a Q-factor of 21 and a full width at half maximum (FWHM) of 53 nm.
• Distinct resonant wavelength shifts were observed for cells infected with different viruses.
• The sensor successfully differentiated between uninfected cells and cells infected with the tested viruses.

Conclusions:

• The proposed micro-nano optical sensor demonstrates high sensitivity and specificity for detecting viral infections.
• The q-BIC and Fano resonance-based approach offers a promising platform for advanced biomedical sensing applications.
• This technology holds potential for future developments in rapid and accurate disease diagnostics.