Interactions between dextran-modified poly(methyl methacrylate) latex particles and concanavalin A

The electrostatic and affinity interactions between concanavalin A (Con A) and dextran-modified latex particles were investigated. The ratio of the in itial number of dextran active sites: to that of Con A molecules plays an i mportant role in determining the structure of flocs formed during adsorptio n and, thereby, has an influence on the amount of adsorbed Con A and the su bsequent elution yield. NaCl and D-glucose, used successively in the two-st ep desorption of Con A, were employed to study the relative importance of e lectrostatic and affinity interactions involved in the Con A adsorption pro cess. A significant fraction of adsorbed Con A is attributed to the electro static interaction mechanism. The feasibility of using the dextran-modified latex products to purify Con A from Jack bean meal was demonstrated.