ELECTROMIGRATION IN SYSTEMS WITH ADDITIVES IN BACKGROUND ELECTROLYTES.2. IONIC ADMIXTURE

A theoretical model is presented for isotachophoretic migration in sys tems where both the leading and terminating electrolytes contain anoth er common component (admixture) (e.g., a difficult to remove impurity) . The effective mobility of the admixture is lower than that of the le ading ion and higher than that of the terminating ion. The model syste m includes a further two samples. The mathematical simulation of the s eparation dynamics of this system was obtained by solution of basic ph ysico-chemical laws. This facilitated a comprehensive formulation of t he principles of the steady state and calculations of the parameters o f all zones. Based on the theoretical model, a method for the determin ation of admixture concentrations in the leading and terminating elect rolytes from isotachophoretic measurements and accurate determination of the limiting mobilities of the separated compounds from experimenta l data affected by the presence of the admixture are described.