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.
Perez-Almodovar
Ernie X
EX
Department of Chemical Engineering, University of Virginia, Charlottesville, VA 22904-4741, USA.
Carta
Giorgio
G
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