Dynamic Methods of Frontal Analysis and Elution-Curve Method to Determine Adsorption Isotherms

摘要

Adsorption isotherm is the most fundamental information related to chromatography process. To calculate the parameters of Langmuir adsorption isotherm, a and b, of thymidine and 5'-GMP, frontal analysis (FA) and elution-curve method (ECM) were adopted in RP-HPLC. In FA, the concentrations of stationary phase were measured from the elution curves and the isotherm was determined by regression analysis, while the parameters of the isotherm in ECM were obtained by optimization method. Comparing between results from the two methods, the adsorption isotherms of thymidine and 5'-GMP were very similar. The superiority of ECM over FA was that the consumption of sample was less and only one or two injections of sample were required.