(461f) Adsorption and Elution of Lectins by Affinity Membranes

Affinity membranes suitable for the purification of lectins were prepared by chemical modifications of a cellulose matrix. Different ligands were tested according to the different affinity towards specific ligands of the lectins used. The affinity of Momordica Charantia lectin towards different carbohydrates was determined by an haemagglutination-inhibition test. Among the various ligands tested carrageenan, arabinogalactan and N-acetyl-D-galactosamine gave the best performances. The reaction between the epoxy group and the ligand has been optimized with respect to concentration of ligand, temperature and reaction time. The effect of the concentration of ligand is not relevant, while temperature is a key parameter on the kinetic of reaction between the epoxy ring immobilized on the membrane surface and the ligand. The ligand immobilized on the membrane surface is quantified indirectly by measuring the amount of protein bound to the membrane. The kinetics of adsorption and desorption of the purification process has been studied in detail for the different supports.