ABSTRACT
The newest optoelectric manipulation technique is termed rapid electrokinetic patterning. Particle capture and sorting with rapid electrokinetic patterning (REP) is a function of the electrokinetic properties. In the absence of the electrothermal microvortex, the dipole-dipole interactions cause the particles to scatter. The electrothermal fluid drag force exerted on trapped particles can be used as an investigative tool for electrokinetic mechanisms. The frequency-dependent polarization of the particles’ ionic double layer has been used to separate particles. Regardless of the model used, the frequency-dependent a-relaxation mechanism can be used to characterize particles on the basis of their size and behavior of their ionic double layer. Colloidal particles suspended in a dielectric medium polarize on the application of an electric field. Particle aggregations are localized to the site of illumination, and hence although REP produces a large aggregation of particles, it has a “local” nature.
