Mass production of cation-exchange cryogels and their chromatographic adsorption performance for bioseparation

The preparation of cryogels with enhanced protein adsorption capabilities holds significant promise in bioseparation. The challenge of industrializing cryogels lies in achieving efficient large-scale production while maintaining controllable performance characteristics. In this work, 200 of poly (hydroxyethyl methacrylate) (pHEMA) monolithic cryogels were mass-produced per batch by cryo-polymerization. Subsequently, 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPSA) was employed as the functional monomer and the cation-exchange pHEMA-AMPSA cryogel discs were successfully prepared by monolith slicing and then stirring graft polymerization. The stable performance of pHEMA cryogel monoliths produced in each batch and the grafting efficacies of pHEMA-AMPSA cryogel discs across different grafting batches were demonstrated to be consistent. An average maximum static adsorption capacity of lysozyme was achieved as 86.5 mg·(mL cryogel discs)^-1, which was higher than those cryogels reported in references. Furthermore, pHEMA-AMPSA cryogel discs were compressed into columns to create cryogel disc-packed beds under different compression ratios, and the effects of compression ratio and loading volume on the chromatographic performance of lysozyme were studied. The dynamic adsorption capacity of lysozyme in cryogel disc-packed bed at a compression ratio of 40 % was five times that of the uncompressed state based on an equivalent volume basis of cryogel discs, reaching 13.1 mg·(mL cryogel bed)^-1 when loading 1 mg mL^-1 lysozyme with a total volume of 355.8 mL. This work offers a simple approach to mass-producing ion-exchange materials with reliable performance and high adsorption capacity for bioseparation industry applications.