Spectral-phase 3D surface plasmon resonance imaging biosensor for COVID-19 neutralizing antibody detection.

Area of Science:

• Biomedical Engineering
• Optical Biosensing
• Immunology

Background:

• Accurate detection of COVID-19 neutralizing antibodies is crucial for disease control and vaccine efficacy assessment.
• Existing detection methods may lack sensitivity, speed, or multiplexing capabilities.

Purpose of the Study:

• To develop and validate a spectral-phase 3D surface plasmon resonance imaging biosensor for sensitive and specific detection of COVID-19 neutralizing antibodies.
• To assess the sensor's performance in terms of resolution and detection limits for SARS-CoV-2 antibodies.

Main Methods:

• Utilized a spectral-phase 3D surface plasmon resonance imaging technique.
• Employed polarization ellipse rotation to convert phase shifts into spectral color information.
• Calibrated the sensor using NaCl solutions and demonstrated multiplex detection of SARS-CoV-2 Omicron spike RBD antibodies.

Main Results:

• Achieved a sensor resolution of 2.3 × 10^-6 Refractive Index Units (RIU).
• Estimated a bio-molecular detection limit of 18.2 pg/µl for antibodies.
• Successfully detected SARS-CoV-2 Omicron spike RBD antibodies, relevant to patient antibody levels.

Conclusions:

• The developed biosensor demonstrates high sensitivity and specificity for detecting COVID-19 neutralizing antibodies.
• This technology holds significant potential for applications in vaccine development, disease surveillance, and point-of-care diagnostics.
• Further advancements could lead to commercialization for public health applications.