Exploiting the Full Potential of Surface Plasmon Resonance: Beyond Sensorgrams and Kinetics to Reflectance Spectra and Surface Layer Characterisation
Abstract
Surface Plasmon Resonance [SPR] has been widely used in biology, providing biophysical data such as affinity, kinetics, and thermodynamics of biological ligands. The main data output has been in the form of a sensorgram, which measures the rate of change in mass at the sensor surface, in terms of the angular change in the position of the Peak Minimum Angle. However, there is a much more powerful approach possible from analysis of the full Reflectance Spectrum collected as part of the SPR data collection process, facilitating the measurement and characterisation of surface layers formed on the sensor surface. The advanced level of analysis available by treatment of the full Reflectance Spectrum of SPR via the Fresnel Equations enables the determination of the transmittance and reflectance properties of the surface coatings, through the Refractive Index and the Extinction Coefficient. This extends the utility of SPR beyond the biological field to materials and coatings, providing a dynamic insight into the mechanism of layer formation. This presentation will present a brief overview from the literature of the different possibilities now available in surface layer analysis with respect to biophysics and surface layer characterisation in a wide range of bio-related applications in material sciences. Moreover, our own data related to the novel application of SPR in studying hydrogen interactions with a sol-gel surface in the context of green energy technology will be presented.
