Computational simulation of migration in free capillary zone electrophoresis I. Description of the theoretical model

An instrument simulator was developed for high-performance capillary electrophoresis which allows for fast graphic illustration of the effect of a large number of variables on the shape of the electropherogram. The input data of the separands are values of pK and mobilities at 25°C and infinite dilution. The instrument parameters that can be varied include capillary material, lengths, inside diameter, wall thickness, zeta potential, cooling temperature, voltage, polarity and open or closed mode. Hydrostatic injection is simulated, using time and pressure as variables. The following properties of the buffer can be varied: pH, ionic strength and effective mobility of background electrolyte ions. The effective mobiities are corrected for temperature and concentration effects. Extra-column effects from injection and detection are taken into account, and also peak dispersion arising from electroosmosis, diffusion, electromigration and heat production.