Plasmonic Contrast Imaging Biosensor for the Detection of H3N2 Influenza Protein-Antibody and DNA-DNA Molecular Binding

Abstract

We report a plasmonic contrast imaging biosensor, RESONATOR. It measures the intensity difference between the p-and s- polarization images at plasmonic excitation. At plasmonic resonance, only the p-polarization light is excited, while s-polarization light remains the same. Image intensity subtraction between both polarizations can eliminate common system noise and enhance sensor resolution. In refractive index measurements, the sensor resolution was found to be $4.36 \times 10^{-7}$ RIU. The plasmonic contrast imaging sensor has further been demonstrated for H3N2 influenza antibody detection and DNA-DNA molecular binding detections. The detection limit was found to be 8.6nM (320 ng mL-1) for H3N2 influenza antibodies. This value is 56% and 216% better than the detection limit reported for influenza antibody detection with commercial Biacore systems. A computer controlled device prototype has further been developed based on the optical design, which is ready for various bio-molecular binding detections in medical diagnosis, drug discovery, biological study and environmental monitoring.