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A simple analytic theory was derived to show that when the electric current was steady, the electro-osmotic flow remained pluglike regardless of the temperature profile inside the capillary due to Joule heating and nonuniform surrounding convection. The temperature-insensitive behavior was caused by the cancellation of the temperature effects.

The block copolymer pluronic F127 and water form a gel-like cubic phase that melts into an easily handled liquid solution. The conformational state and the mode of electrophoretic migration of double stranded DNA in the cubic gel are studied.

The importance of the ionic size correlations with electrophoretic mobility is measured as a function of surface charge density. The results are compared with theoretical predictions to estimate the weight of the ionic size correlations in this kind of system.

It is generally agreed that the interaction between poly(ethylene glycols) and sodium dodecyl sulfate-poly(acrylamide) (SDS) arises at three distinct levels. There is no interaction between the polymer and the surfactant at low SDS concentrations.

Research is presented describing the methods used to carry out experiments using steady-state electrophoresis.

A study uses a cell model to derive the electrokinetic equations for salt-free suspensions with special emphasis in electrical conductivity and electrophoretic mobility, and revises and compares it with previous salt-free electrophoresis models. Results demonstrate that the electrophoretic mobility and also the conductivity are practically unchanged if a complete boundary condition is used instead of the approximated one.

A cubic liquid crystal formed by the nonionic monoglyceride monoolein and water as a porous matrix is used for electrophoresis of oligonucleotides. The cubic phase formed by monoolein and water is capable of separating oligonucleotides according to size, secondary structure and flexibility, but the slow migration means that the main interest in the cubic phase is not a replacement for conventional gels.

A floating-potential dielectrophoresis method used for the first time to achieve controlled alignment of an individual semiconducting or metallic single-walled carbon nanotube (SWCNT) between two electrical contacts with high repeatability is presented. The results indicate that bundles of carbon nanotubes along with impurities were first moved into the region between two control electrodes while an individual nanotubes without impurities were straightened and aligned between two floating electrodes.

A quantitative predictive model of the electrophoretic mobility of a bent molecule of cylindrical symmetry relative to a straight one in a gel is discussed. The predictions are compared with available experimental data as well as semiempirical relation between the relative electrophoretic mobility and the bend angle by Thompson and Landy.

Capillary electrophoresis (CE) is performed on polymer-stabilized bundles and sodium dodecyl sulfate (SDS) suspensions of high-pressure carbon monoxide (HiPco)-produced single-walled carbon nanotubes. Separation on SDS suspensions indicates that CE is capable of separating bundled nanotubes from isolated individuals on the basis of differences in nanotube mobility.

The specific effect of the overlapping of double-layer on the electrophoretic mobility and DC electrical conductivity of a concentrated suspension of spherical colloidal particles is considered. The results show that the double-layer overlapping corrections lead to an important estimation of the true values of both the electrophoretic mobility and the electrical conductivity

The boundary effect on the electrophoretic behavior of a particle is investigated theoretically by considering a finite, charged, cylindrical particle in an uncharged cylindrical pore for the case of low electrical potential. Results show that the mobility decreases with the increase in the aspect ratio (particle radius/particle length) of the particle.

The behavior of DNA in KCl and Tris acetate to understand the difference in the electrophoretic mobility under different conditions is examined. Results show complex formation occurs not only between DNA and buffer but also between DNA and neutral salts.

The sedimentation of a nonconducting spherical particle in a spherical cavity is analyzed theoretically. It is shown that, for the case where the former is positively charged and the latter uncharged, the sedimentation velocity of the particle decreases with ka, k and a being respectively the reciprocal Debye length and the radius of the particle.

Research was conducted to examine the dielectrophoretic response of submicrometer particles as a function of electrolyte conductivity and composition, particle size and applied field frequency. Experimental results were compared with the classical theory of the dielectrophoretic force obtained from Maxwell-Warner interfacial polarization. Findings reveal that measurements of the dielectrophoretic nature of single submicrometer latex particles can be employed to uniquely characterize their dielectric properties.