چكيده به لاتين
Modeling of electrophoresis as a common separation, detecting, sorting and sequencing method used in micro/nano fluidic system has attracted lots of attentions. Each day a new analytical and semianalytical expressions is suggested by the scientists for description of the electrophoretic behavior of charged particles, which improves the accuracy of the former expressions. However, it can be said that there still exist some phenomena overlooked in modeling electrophoresis. In this thesis, we have taken into account the effect of ion partitioning phenomena on the electrophoresis soft particles, i.e. rigid spherical particles covered with a polyelectrolyte layers (PEL). Ion partitioning steming from the fact that the electrolyte movable ions prefer to stay inside the medium of higher dielectric permittivity, is a common phenomena taking place in the cases that the PEL is either very dense, or been made up of molecules of very low dielectric permittivity. We have devided this project into three phases: first we have studied the effect of ion partitioning on the electrostatics of the soft particles and the movable ions arrangement. Then, in the second phase, the electrophoretic mobility of soft particles under the influence of ion partitioning and in the absence of any external wall has been studied. Ultimately, in the third phase, the effect of ion partitioning on the capillary electrophoresis of soft particles is investigated. Briefly, we have found that ion partitioning leads to a significant rise in the electric potential inside the PEL and makes the concentration profile discountinous. The impact of ion partitioning on the electrostatics of weak soft particles was found to be more notable, as in such systems besides the ions arrangement, the charge of the PEL is a function of ion portioning. Finally, the electrophoretic mobility both in unbounded medium and inside the capillaries was found to be increased as a result of ion partitioning. This was attributed to the fact that the decrease in the ions concentration inside the PEL region leads to the decrease of the shielding effect of the particle charge. According to the results gained, this research strongly recommends inclusion of ion partitioning effect in the calculations of electrophoresis especially in the cases of dense PEL.