A NEW METHODOLOGY FOR ESTIMATION OF SECOND ORDER REVERSIBLE INTERACTION APPARENT ADSORPTION AND DESORPTION RATE CONSTANTS OF PROTEIN BINDING KINETICS ONTO RESINS IN PACKED-BED COLUMNS

摘要

In this study, a simple and effective technique for characterizing apparent kineticparameters of protein adsorption in a recycled packed bed column (RPBC) is presented.The apparent kinetic parameters of bovine serum albumin (BSA) onto a weak base ionexchange resin (Duolite A 568) were estimated in a recirculation system. Reservoir BSAconcentrations were obtained for different column flow rate, column L/D ratio and initialcolumn feed BSA concentration, and the governing mathematical equations based onkinetic rate constant model were numerically solved employing an implicit finite differencemethod. The effects of these operational parameters on the adsorption performance weredetermined only by monitoring reservoir BSA concentration. It was observed that, withincreasing flow rate up to an upper limit film resistance decreased and apparent forwardadsorption rate kf, increased, while increasing flow rate any further decreased kf due toinsufficient contact time and enforced compressibility. While kf was significantly enhancedat higher column L/D ratios under fixed operational conditions, increasing feed BSAconcentration decreased kf at high volumetric flow rates most likely due to decreased BSAdiffusion rate. The presented model is easily applicable to estimate column performanceunder a wide range of operating conditions and does not require the simultaneousmeasurement of inlet and outlet protein concentrations of the column.