▎ 摘　　要

The present paper analyses a surface plasmon resonance (SPR) biosensor based on graphene that leads to improvement on the efficiency of an urea biosensor due to high adsorption. Kretschmann configuration is well known as the most effectively used technique for plasmon excitation. In this work, we investigated the effect of MoS2 with a fine layer of graphene deposited on a plasmonic material, gold (Au), into the configuration. Simulation is based on finite-difference time domain (FDTD) method for analysis. The performance of SPR biosensor can be monitored by analyzing the sensitivity and full width-at-half-maximum (FWHM) of the SPR spectrum. The measurements are observed at 670 and 785 nm for urea detection. The molarity and refractive index is varied from 1.335 to 1.342 for the sensing layer. The results showed that the percentage increase in sensitivity for the proposed biosensor Au/MoS2/graphene over conventional biosensor Au is 98% and 202% at 670 and 785 nm, respectively, which indicates that the proposed novel SPR biosensor is better suited for urea detection.