Dielectrophoretic behavior of latex nanospheres: Low-frequency dispersion

The electrostatic manipulation of nanoparticles using nonuniform electric fields (dielectrophoresis) has proved a useful method of investigating the movement of charge around colloidal particles. While previous work has explained many of the ways in which particle behavior deviates from that predicted by classical Maxwell-Wagner interfacial polarization theory, there exists an additional, anomalous polarization mechanism observed in media of high conductivity, causing an unexpected observation of positive dielectrophoresis. Here this is suggested that this may be explained in terms of the polarization of the Stern layer. (C) 2002 Elsevier Science (USA).