On the Field Enhancement and Performance of an Ultra-Stable SPR Biosensor Based on Graphene

The effect of graphene on the electric field enhancement and performance of SPR-based sensor has been proposed and compared with Ag-Au bimetallic configuration. We found that a monolayer of graphene on Ag not only addresses the oxidation problem of Ag, but it also shows >30% field enhancement as compared with the widely reported Ag-Au bimetallic combination. Detailed calculations and simulations show that the proposed graphene-based sensor has >22% higher sensitivity and >38% narrower full-width at half-maximum than bimetallic. In addition, the better biomolecules adhesion due to graphene because of p-stacking interaction may open a new window for ultra-stable high performance biosensors for real time bimolecular interactions.