Impact of double cryogelation process on a macroporous dye‐affinity hydrogel

Abstract

Cryogels with interconnected channels allow high flow‐through properties and mass transfer when dealing with complex mixtures such as non‐clarified crude extracts. However, their mechanical strength can be challenged due to a large void volume inside the polymeric network. We have addressed this problem by forming a double‐layer cryogel applied as a dye‐affinity chromatography gel. In this study, poly(acrylamide‐co‐allyl glycidyl ether) cryogel was prepared at sub‐zero temperature. The second layer was then prepared inside the primary cryogel under the same conditions to form a double‐layer network. Cibacron Blue F3GA, a dye molecule, was immobilized on the surface of the cryogels. Bovine serum albumin was used as a model molecule to study the adsorption/elution procedure in batch and continuous modes. The maximum batch binding capacity and the dynamic binding capacity for the single‐layer cryogel were 18 and 0.11, and for the double‐layer cryogel were 7.5 and 0.9 mg/g of gel, respectively. However, the mechanical stability of the double‐layer cryogel increased 7‐fold (144 kPa). It was found that the kinetic and adsorption isotherms follow pseudo‐second‐order and Freundlich models, respectively. The regeneration of the columns after adsorption/elution cycles was evaluated, and no significant loss of capacity was observed after 10 cycles.