In this lecture, we continued the SPR Sensors discussion. We started off with the coupling condition being determined by the refractive index. This means that light now goes through a protein. In the experimental results, it shows a shift from lower angle to a higher angle that resulted in the coupling condition. Then we looked at three different methods to use the Kretschmann Geometry to look at measuring SPR. The first method was to use a lens to measure all of the angles, the second was to use white light to represent all of the wavelengths, and the last method was to use a laser and look at the intensity of the reflection through a photodiode. The results of the biosensor are then presented on a graph called a "sensorgram". We then looked at the different assay methods, including direct binding assay and inhibition assay. Last, we discussed the disadvantages of the Kretschmann Geometry. We could only measure a handful of independent sensor location and we index matching coupling fluid to interface sensor chip to prism.
University of Illinois at Urbana-Champaign, Urbana, IL