title: Double sequential modifications of composite cryogel beds for enhanced ion-exchange capacity of protein.
abstract: Composite cryogel monoliths based on poly(2-hydroxyethylmethacrylate) (pHEMA) were fabricated by incorporating polymeric resin particles. The monoliths were sequentially modified by polyethylenimine (PEI) and diethylaminoethyl (DEAE). The novel composite material had rough pore walls and extended anion-exchange tentacles, which provided more binding sites for protein molecules. The dynamic adsorption capacity of bovine serum albumin (BSA) on the novel cryogel bed reached 11.2mg/mL bed volume at a flow velocity of 8cm/min, which was about 1.5-4.6 times higher than the cryogel beds obtained by single modifications. The capacity value was also much higher than the BSA capacities of cryogel beds reported in literature (1-6mg/mL). The capacity decreased only slightly with increasing flow rate from 0.6 to 12cm/min. The height equivalent to a theoretical plate of the composite beds was in the range 2-2.5mm, changed indistinctively in a flow rate range 0.6-18cm/min. Hence, the work has proved that the double-modification strategy was promising for enhancing protein adsorption capacity of cryogel monolith for high-speed protein chromatography.
authors.affiliation: Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Sun
mesh_terms: D000327:Adsorption; D000818:Animals; D002417:Cattle; D002852:Chromatography, Ion Exchange / Q000295:instrumentation* / Q000379:methods; D059985:Cryogels / Q000737:chemistry*; D011312:Pressure; D011485:Protein Binding; D011506:Proteins / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification; D012710:Serum Albumin, Bovine / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D059985:Cryogels; D011506:Proteins; D012710:Serum Albumin, Bovine
keywords: Adsorption capacity; Anion-exchange; Composite cryogel; Double-modification; Particle-embedding; Protein chromatography