DEP works by exploiting the differences in the polarizability of particles within an electric field. The force acting on a particle depends on the particle's dielectric properties, the medium's properties, and the electric field gradient. The equation governing DEP force is:
F_DEP = 2πr³ε_m Re[f_CM] ∇E²
where r is the radius of the particle, ε_m is the permittivity of the medium, f_CM is the Clausius-Mossotti factor, and ∇E² is the gradient of the squared electric field.
