Preparation and characterization of adsorbents for use in high-performance liquid affinity chromatography

Abstract

Adsorbents suitable for use in high-performance liquid chromatography were produced by covalently immobilizing Procion Blue MX-R to microporous silica. The adsorption capacities of the resulting materials were investigated. It was found that a Langmuir isotherm gave the best fit to data obtained for the adsorption of lactate dehydrogenase, while a Freundlich isotherm best described adsorpion of lysozyme. A 12-μm diameter silica with 28-nm diameter pores and a bound ligand concentration of 7 μmol (Procion Blue MX-R)/g (silica) had a capacity of 8.7 mg (lactate dehydrogenase)/g and 40.0 mg (lysozyme)/g. The rate of the overall adsorption process was found to be rapid. A model which assumes instantaneous equilibrium between solid and liquid phases was used to describe chromatography performed on these adsorbents. This gave a good approximation to the breakthrough and washout profiles.