Numerical analysis of graphene coated surface plasmon resonance biosensors for biomedical applications

This paper describes the effect of adding graphene layers in prism and planar waveguide based surface plasmon resonance biosensors using angular interrogation mode. The proposed sensors are designed based on graphene material as biomolecular recognition elements (BRE) and the sharp SPR curve of gold (Au). Our calculations show that the proposed graphene in prism and planar waveguide based SPR biosensors have 1 + 0.40 L and 1+0.45 L; (where L is the number of graphene layers) times more sensitivity than the conventional SPR biosensor respectively. The enhanced sensitivity is due to increased SPR angle change about 40 L% and 45 L% by adding graphene layer and using the optical property of graphene. We also investigate the performance of proposed biosensors in terms of sensitivity using graphene sublayers. The compact size, prism and planar waveguide based design, and very high sensitive- these characteristics are expected to make these biosensors preferred choice for biomedical applications, as compared to other contemporary biosensors.