Modeling the Electropherogram of Small Charged Molecules in Capillary Zone Electrophoresis

− A model for capillary zone electrophoresis (CZE) is presented to carry out the method development of practical separations involving small charged molecules. The model is based on principles and dynamic equations that contain true physicochemical properties of electrolyte solutions and analytes. The basic variables considered in the model are: injection and detection lengths of analytes, electrical field strength, hydration radius and diffusion coefficient of analytes, pK of analyte terminal groups, pH and ionic strength of electrolyte solution, capillary diameter and length, capillary zeta potential, test temperature and relative mass fractions of analytes. The model is solved numerically to predict the separation of analytes through the resulting electropherogram, which is then compared with experimental data. Keywords− Capillary Zone Electrophoresis, Electropherogram Modeling, Small Charged Molecules, Hydration Radius, Capillary and Particle Zeta Potentials.