IgG adsorption on a new protein A adsorbent based on macroporous hydrophilic polymers II. Pressure-flow curves and optimization for capture.
Pressure-flow curves are obtained for a new protein A adsorbent matrix based on macroporous hydrophilic polymer beads with average diameter of 57 microm and a narrow particle size distribution. Experimental data are obtained in a 1cm diameter laboratory column and in preparative scale columns with diameters of 20, 30, and 45 cm. The results are consistent with a model that assumes a linear relationship between bed compression and relative flow velocity. Surprisingly, the packing compressibility is essentially independent of column diameter for the preparative columns. As a result, after accounting for the variation in extraparticle porosity caused by compression, the column pressure drop is accurately predictable using the Carman-Kozeny equation. A model is also developed to predict productivity for IgG capture as a function of operating conditions based on dynamic binding capacity data presented in Part I of this work. For typical conditions, the model predicts maximum productivity at low residence times, between 1 and 1.5 min, when the dynamic binding capacity is at about 70-80% of the maximum. Combining the two models for column pressure and for dynamic binding capacity allows the design of preparative scale columns that maximize productivity while meeting specified pressure constraints.
Department of Chemical Engineering, University of Virginia, Charlottesville, VA 22904-4741, USA.
Ernie X
EX
Perez-Almodovar
Giorgio
G
Carta
D002845:Chromatography / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D007074:Immunoglobulin G / Q000737:chemistry* / Q000378:metabolism; D008956:Models, Chemical; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D011312:Pressure; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D013205:Staphylococcal Protein A / Q000737:chemistry* / Q000378:metabolism
D007074:Immunoglobulin G; D011108:Polymers; D011994:Recombinant Proteins; D013205:Staphylococcal Protein A