Continuum model of dielectrophoretic particle transport

Here we present a purely continuum model of dielectrophoretic particle separations and transport that can accurately predict particle transport even into the nanoscale. These techniques can be modified to precisely forecast and direct particle motion at the nanoscale, allowing for the efficient and highly specific separation of nanoparticles in a variety of applications. As particles move through nanoscale systems, they are affected by various inputs such as fluid velocity, electric fields, and particle interactions with surfaces. This model takes as input particle solution permittivity and predicts spatial distribution of particle concentration. We will present a facile method for measuring the permittivity of solutions using a microfluidic device and then use this data to simulate the 2D distribution of particles within a channel with well-defined electric field gradients. The experimental data are compared to this simulation, which uses fluorescent polystyrene particles of varied diameters ranging from the nanoscale to the microscale.