Stochastic time response of adsorption-based micro/nanobiosensors with a fluidic reaction chamber: The influence of mass transfer

An approximate model for efficient analysis of stochastic time response of microfluidic biosensors is presented, that considers a random AD process coupled with mass transfer (convection and diffusion) of target substance particles. The deterministic model of sensor response is also reviewed. We perform the analysis of the mass transfer influence on the kinetics and the steady-state value of the response calculated according to the two models (deterministic and stochastic). The results are presented for the sensors with different micro/nanoscale active surfaces. The comparison of the responses obtained by using the two models can be utilized to distinguish the cases in which the application of the deterministic model is justified from those in which the stochastic model is necessary. The presented findings enable more accurate interpretation of measurement results obtained by using micro/nanobiosensors.