  In this paper we report a semianalytical model of the mass transfer impedance
in microfluidic electrochemical chips (MEC). It is based on the molar advection
diffusion equation in a microfluidic channel with a Poiseuille flow and an
electrochemical reaction at the interface of deposited electrodes. Using the
Fourier-Laplace integral transforms and the quadrupole formalism, a solution to
these equations is found and the three dimensional (3D) transient concentration
and current density fields are computed. This solution is validated using MFC
operando concentration fields measured by visible spectroscopic imaging
technique, and several equivalent electrical circuits are also proposed to
model the mass transfer in MEC. This work reports the fastest way to compute
the 3D transient mass transfer impedance which can be used in large variety of
applications such as MEC based cytometry measurements or fuel cell current
density prediction.
