title: High capacity cryogel-type adsorbents for protein purification.
abstract: Cryogel bodies were modified to obtain epoxy groups by graft-copolymerization using both chemical and gamma irradiation initiation techniques. The free epoxy adsorbents were reacted further to introduce diethylaminoethanol (DEAE) functionalities. The resulting weak anion-exchange cryogel adsorbents showed dynamic binding capacities of ca. 27±3mg/mL, which was significantly higher than previously reported for this type of adsorbent material. Gamma irradiated grafting initiation showed a 4-fold higher capacity for proteins than chemical grafting initiation procedures. The phosphate capacity for these DEAE cryogels was 119mmol/L and also showed similar column efficiency as compared to commercial adsorbents. The large pores in the cryogel structure ensure convective transport of the molecules to active binding sites located on the polymer-grafted surface of cryogels. However, as cryogels have relatively large pores (10-100μm), the BET area available for surface activation is low, and consequently, the capacity of the cryogels is relatively low for biomolecules, especially when compared to commercial beaded adsorbents. Nevertheless, we have shown that gamma ray mediated surface grafting of cryogel matrices greatly enhance their functional and adsorptive properties.
authors: Downstream Bioprocessing Laboratory, School of Engineering and Science, Jacobs University, Campus Ring 1, D-28759 Bremen, Germany.
authors: Naveen Kumar
authors: NK
authors: Singh
authors: Downstream Bioprocessing Laboratory, School of Engineering and Science, Jacobs University, Campus Ring 1, D-28759 Bremen, Germany.
authors: Roy N
authors: RN
authors: Dsouza
authors: Laboratorio de Materiales Biotecnológicos, Depto. de Ciencia y Tecnología, Universidad Nacional de Quilmes, Roque Sáenz Peña 352 (B1876BXD), Bernal, Argentina.
authors: Mariano
authors: M
authors: Grasselli
authors: Downstream Bioprocessing Laboratory, School of Engineering and Science, Jacobs University, Campus Ring 1, D-28759 Bremen, Germany. Electronic address: m.fernandez-lahore@jacobs-university.de.
authors: Marcelo
authors: M
authors: Fernández-Lahore
mesh_terms: D000327:Adsorption; D002848:Chromatography, DEAE-Cellulose / Q000379:methods*; D059985:Cryogels / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D058105:Polymerization; D011108:Polymers / Q000737:chemistry; D016062:Porosity; D011506:Proteins / Q000302:isolation & purification*
chemical_list: D059985:Cryogels; D011108:Polymers; D011506:Proteins
keywords: Dynamic binding capacity; Megaporous cryogels; Monoliths; Protein chromatography; Weak anion-exchange