Molecular Dynamics Simulation to Determine Dopamine Binding Mechanisms on MXene Surfaces

MXenes have a variety of potential applications due to their conductivity and atomic thickness, including batteries, composites, and sensors. Their use as dopamine sensors is dependent on the surface termination, concentration, temperature, and pH. However, determining the mechanisms of dopamine binding experimentally is difficult and expensive due to the scale of these molecules and surfaces. Classical molecular dynamics using the Interface Force Field and CHARMM can simulate MXene systems with dopamine at the single-atom scale. This model is compatible for MXenes and dopamine with a variety of surface terminations and pH. Simulations with easily adjusted pH, surface termination, concentration, and temperature calculate the binding energy, equilibrium binding concentrations, and residence times for single dopamine molecules and multiple-dopamine systems. These simulations provide insight into the mechanisms of attachment, detachment, and accumulation, guiding future design of biosensors.