High-speed spinning-disk interferometry on the BioCD for human diagnostic applications

Area of Science:

• Biomedical Engineering
• Optical Biosensing
• Nanotechnology

Background:

• Direct detection of antigen binding in protein arrays is crucial for diagnostics.
• Existing methods face trade-offs between multiplexing capability and detection limits.
• High-resolution metrology is needed for sensitive surface-bound protein measurement.

Purpose of the Study:

• To demonstrate quantitative assays using the BioCD optical biosensor.
• To evaluate the scaling properties of direct detection on the BioCD.
• To assess the BioCD's performance in clinically relevant human diagnostic assays.

Main Methods:

• Utilizing high-speed spinning-disk interferometry for direct antigen detection.
• Employing high-frequency sampling to minimize noise and achieve picometer-level height resolution.
• Performing multiplexed immunoassay protein array analysis.

Main Results:

• Demonstrated quantitative assays for haptoglobin and prostate-specific antigen (PSA).
• Achieved metrology-limited height resolution of 1 picometer for surface-bound proteins.
• Validated the BioCD's performance in human patient sera.

Conclusions:

• The BioCD enables sensitive and quantitative direct detection of proteins in complex biological samples.
• The technology overcomes the multiplexing vs. limit of detection trade-off.
• BioCD shows significant potential for advancing human diagnostics.