DYNAMICS OF PEAK DISPERSION IN CAPILLARY ZONE ELECTROPHORESIS INCLUDING WALL ADSORPTION .2. EXACT ANALYSIS OF UNSTEADY LINEAR ADSORPTIVE DISPERSION

An exact analysis of the unsteady axial dispersion of an analyte, undergoing a linear adsorption at the column wall in capillary zone electrophoresis, is presented. A system of partial differential equations - in which the radial coordinate is one of the independent variables - is taken as a model for linear wall adsorption. It is shown that the dispersion is a sum of two terms, one which depends linearly on time and whose exact form is generally known, and a nonlinear one. The most interesting result of this work is that it derives another system of differential equations, which this nonlinear term is to satisfy. It makes it possible to present a closed formula for the asymptotic value of the nonlinear term, i.e., its limit for large time. Its behavior for times close to zero is also studied.