{Reference Type}: Journal Article {Title}: Study of behavior of carboxylic magnetite core shell nanoparticles on a pH boundary. {Author}: Cacho C;Marková Z;Ševčík J;Zbořil R;Petr J; {Journal}: J Chromatogr A {Volume}: 1364 {Issue}: 0 {Year}: Oct 2014 17 {Factor}: 4.601 {DOI}: 10.1016/j.chroma.2014.08.090 {Abstract}: During the last years, several authors have focused on the characterization of the size and charge of the nanoparticles by capillary electrophoresis. However, considering that nanoparticles are generally suspended in a solvent different from those commonly used as background electrolytes (BGE), an appropriate characterization of the behavior of the nanoparticles in the sample-BGE interface is required, as this might affect the overall electrophoretic behavior of the nanoparticles. In the present work, we address the evaluation of the behavior of COOH-coated maghemite nanoparticles in the vicinity of a pH boundary. To do so, different suspensions of nanoparticles prepared in acid media were injected into a borate/NaOH pH 9.5 BGE. The formation and evolution of boundaries in the sample-BGE interface in such systems was modeled by computer simulation. A systematic evaluation of the effect that parameters such as the co-ion, the sample pH or the injection time have on the electrophoretic behavior of the nanoparticles was carried out.