Stotz-Wien Effect

Aperiodic electrophoresis refers to the use of an unbalanced AC field to separate charged polarizable particles due to the Stotz-Wien effect of field-dependent electrophoretic mobility. 

In the 1970s, S. S. Dukhin s group was perhaps the first to recognize that the electrophoretic mobility of polarizable particles must generally depend on the electric field [9]. In a series of Russian papers, which have yet to gain widespread attention, they predicted perturbations of the mobility as AZ oc and thus nonlinear electrokinetic motion At/ oc, which they have come to call the Stotz-Wien effect. For the case of a steady weak field applied to an ideally polarizable sphere of radius a, A. S. Dukhin derived an expansion for the mobility ... 

In principle, the Stotz-Wien effect can be used to separate colloidal particles using an unbalanced AC field, which has zero time average (E) = 0, but nonzero time-averaged higher moments, such as (E )/=0. An unbalanced AC field leads to a size-dependent nonlinear... 

The first experiments demonstrating field-dependent electrophoretic mobility of colloids (Stotz-Wien effect) were reported by several... 

The Stotz-Wien effect refers to the dependence of the electrophoretic mobility of a charged polarizable particle on the field strength due to induced-charge electroosmotic flow. 

Stotz-Wien effect. For the case of a steady weak field applied to an ideally polarizable sphere of radius a, A.S. Dukhin derived an expansion for the mobility. 

The first experiments demonstrating field-dependent electrophoretic mobility of colloids (Stotz-Wien effect) were reported by several groups in the 1970s [14], and the possibility of using this effect for particle separation using unbalanced AC fields has begun to be explored [14]. This work focused on nonlinear corrections to the classical phenomenon of electrophoresis, where a particle moves in the direction of the applied electric field, U = b(E)E, rather than on the associated ICEO flows and more complicated ICEP motion. 

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