Evaluation of electric field in polymeric electrodes geometries for liquid biosensing applications using COMSOL multiphysics

Abstract

This work investigates the electrical field distribution in polymeric electrodes, materials composed of polymers and nanoparticles that leverage the physicochemical interactions between constituents to modify mechanical and electrical properties. Polymeric matrices often incorporate carbon nanoparticles to impart specific conductive properties while simultaneously enhancing mechanical stability through a protective polymer layer. The morphology, dielectric properties, and geometric configuration of these materials influence the electric field distribution, which is critical to their functionality. Utilizing finite element modeling, this study not yet explored aims to predict these effects and guide the design of material compositions and structural geometries to optimize functionalities like catalytic activity, adhesion enhancement, and interface energy reduction. Simulations were conducted using COMSOL 6.0 across eight similar geometric configurations, assessing polarization, and electric potential distribution. Results underscore the importance of surface polarization in controlling roughness and optimizing biosensor performance for liquid samples. Notably, controlled surface roughness induces asymmetric electric field distortions at biosensor edges, influencing dipole moments in polarizable nanoparticles. Each tested geometry demonstrated unique characteristics pertinent to its application in 3D-printed biosensors, influenced by surface roughness and wettability. Additionally, modifications in the electrical double layer due to controlled roughness alter charge distributions at the electrode-electrolyte interface, affecting electric field configurations.