Preparation and characterization of high capacity, strong cation-exchange fiber based adsorbents.
Motivated by the demand for more economical capture and polishing steps in downstream processing of protein therapeutics, a novel strong cation-exchange chromatography stationary phase based on polyethylene terephthalate (PET) high surface area short-cut fibers is presented. The fiber surface is modified by grafting glycidyl methacrylate (GMA) via surface-initiated atom transfer radical polymerization (SI-ATRP) and a subsequent derivatization leading to sulfonic acid groups. The obtained cation-exchange fibers have been characterized and compared to commercially available resin and membrane based adsorbers. High volumetric static binding capacities for lysozyme (90mg/mL) and polyclonal human IgG (hIgG, 92mg/mL) were found, suggesting an efficient multi-layer binding within the grafted hydrogel layer. A packed bed of randomly orientated fibers has been tested for packing efficiency, permeability and chromatographic performance. High dynamic binding capacities for lysozyme (50mg/mL) and hIgG (54mg/mL) were found nearly independent of the bed-residence time, revealing a fast mass-transport mechanism. Height equivalent to a theoretical plate (HETP) values in the order of 0.1 cm and a peak asymmetry factor (AF) of 1.8 have been determined by tracer experiments. Additionally inverse size-exclusion chromatography (iSEC) revealed a bimodal structure within the fiber bed, consisting of larger transport channels, formed by the voidage between the fibers, and a hydrogel layer with porous properties.
Sartorius Stedim Biotech GmbH, August-Spindler-Strasse 11, 37079 Göttingen, Germany; Institute for Separation and Process Technology, Clausthal University of Technology, Leibnizstrasse 15, 38678 Clausthal-Zellerfeld, Germany. Electronic address: jan.schwellenbach@sartorius-stedim.com.
Jan
J
Schwellenbach
Sartorius Stedim Biotech GmbH, August-Spindler-Strasse 11, 37079 Göttingen, Germany.
Florian
F
Taft
Sartorius Stedim Biotech GmbH, August-Spindler-Strasse 11, 37079 Göttingen, Germany.
Louis
L
Villain
Institute for Separation and Process Technology, Clausthal University of Technology, Leibnizstrasse 15, 38678 Clausthal-Zellerfeld, Germany.
Jochen
J
Strube
D000327:Adsorption; D002412:Cations; D002852:Chromatography, Ion Exchange / Q000295:instrumentation* / Q000379:methods; D004852:Epoxy Compounds / Q000737:chemistry; D006801:Humans; D020100:Hydrogels; D007074:Immunoglobulin G / Q000032:analysis; D008689:Methacrylates / Q000737:chemistry; D009113:Muramidase / Q000032:analysis; D010539:Permeability; D011093:Polyethylene Terephthalates / Q000737:chemistry*; D058105:Polymerization; D013451:Sulfonic Acids / Q000737:chemistry
D002412:Cations; D004852:Epoxy Compounds; D020100:Hydrogels; D007074:Immunoglobulin G; D008689:Methacrylates; D011093:Polyethylene Terephthalates; D013451:Sulfonic Acids; D009113:Muramidase; C007870:glycidyl methacrylate
Atom transfer radical polymerization; Ion-exchange; Protein adsorption; Stationary phase; Surface modification