Breakthrough curve performance using plate-and-frame affinity-membrane modules

The effects of inlet flow rate on the breakthrough curve performance of lysozyme using plate-and-frame dye-affinity-membrane modules were investigated in this work. For the nonadsorption results, it is found that the influences of flow rate on both permeate and retentate breakthrough curves mainly came from the flow maldistribution and extra-module mixing effects. On the other hand, the effects of axial and radial diffusion were negligible in this case. When single-protein adsorption occurred, the elution peak height in the permeate decreased with increasing flow rate, which resulted from the limitation of convective flow. Moreover, this study investigated three larger-scale designs: a multiple-membrane stack in one module, two modules connected in parallel, and two modules in tandem. Both of the two-module designs resulted in a greater amount of eluted protein, which is attributed to their lower flow rates in the modules than the multiple-membrane-stack design. As for the two-protein breakthrough curve performance, a simple separation of lysozyme from nonadsorbable bovine serum albumin (BSA) was observed but the existence of BSA declined the lysozyme adsorption. The degree of influence on lysozyme adsorption was the same in both one-module and two-module-in-tandem designs. Furthermore, the recovered percentages of lysozyme in both one-module and two-module designs were low, and this was mainly restricted by the limitation of flow rate for the membrane modules adopted in this study.