Surface Plasmon Resonance-Based Fiber-Optic Metallic\nMultilayer Biosensors

Abstract

Accurate and quick\nsensing of various biomolecules relevant to\ndifferent health conditions is indispensable in modern diagnosis and\ntreatment procedures. Different multilayer metallic surface plasmon\nresonance (SPR) biosensor configurations comprising Au, Ag, Al, and\nCu are analyzed in this work by employing an <i>N</i>-layer\nmatrix formalism as applied to the fixed-angle spectral SPR sensing\nmethodology. Stringent standards for sensitivity, detection accuracy,\nand figure of merit (FOM) of the sensor configurations are set to\nanalyze the relative merits of one configuration over another. It\nis observed that three- and four-layer configurations using Al and\nCu provide the best FOM among all sensors that passed the set standard\ncriteria. The highest FOM (1433.82/RIU) is observed for the four-layer\nAl/Cu/Al/Cu sensor for an analyte refractive index of 1.408. The sensors\nare best suited for detecting analytes with a refractive index range\nof 1.350–1.414.