Polymer based surface plasmon resonance sensors: Theoretical study of sensing characteristics

Abstract

There has been renewed interest in the area of surface plasmon resonance (SPR) for biosensing application. The analytical tools such as immunofluorescence, chromatography and mass spectroscopy are laboratory based and require considerable amount of time and expense and their overall use is complicated. SPR based sensing is a promising technique with the advantage of high sensitivity, small size, easy to use and not so expensive. Due to the need for easy processing and low cost sensing design, polymers can be considered as a favorable candidate for designing the SPR sensors. Ease of fabrication, disposability and cost-effectiveness are some of the merits of polymer materials that make them an ideal for the sensor. The present work investigates exclusively the effect of different polymeric materials on the sensitivity of SPR. Theoretical calculations are done in reflectance mode. Any change in refractive index of analyte results in the angular shift of reflectance dip that can be utilized to detect the presence of analyte. Different multilayer SPR configurations are modeled in Matlab to investigate the optical characteristics of the sensor. In addition, the optimal parameters of different layers corresponding to the highest sensitivity are explored. The performance of an SPR sensor is determined by its sensitivity (Sθ), FWHM and Rmin.