Adsorption of proteins on Sepharose affinity adsorbents of varying particle size

The binding of bovine serum albumin (BSA) and lysozyme to a series of samples of Cibacron Blue F3G-A Sepharose CL-6B with different narrow-range mean particle diameters has been investigated. Significant variation with particle size has been found for the parameters measured. For both proteins the maximum capacities obtained increased with decreasing particle size. For lysozyme, this percentage increase in capacity is less than the percentage increase in external surface area as the particle size decreases. For BSA, however, the percentage increase in capacity is more than four times the increase in surface area. The dissociation constants and forward rate constants describing the affinity interaction also differ with particle size. Again the effects are more pronounced for the larger protein, BSA, than for lysozyme. The effect of these differing parameters on the performance of fixed beds has been assessed using a computer simulation of the adsorption process.