Advanced terahertz-range dopamine detection using a 2D material-based metasurface biosensor

This study presents an innovative terahertz-range dopamine detection sensor utilizing a metasurface architecture incorporating graphene, borophene, and phosphorene. The sensor design features a 2 µm square resonator coated with phosphorene, surrounded by four 1 µm borophene-coated circular resonators on a 16µ<i>m</i>×16µ<i>m</i> graphene platform. The numerical findings in the present study are essentially investigated based on the fundamentals of the finite element method through COMSOL Multiphysics software. The sensor demonstrates consistent operation across two frequency bands (0.1-0.3 THz and 1.2-1.6 THz), with tuning ranges of 16 and 70 GHz, respectively. Meanwhile, the performance analysis reveals an exceptional sensitivity of 500 GHz/RIU, with a figure of merit of 8.333 and a detection limit of 0.223. Additionally, we have conducted a machine learning optimization using polynomial regression, achieving <i>R</i>² values exceeding 0.92, to validate the design's reliability. Therefore, we believe that the proposed sensor offers a practical solution for dopamine detection, combining high sensitivity with fabrication feasibility for potential commercial applications.