Investigation of lysozyme adsorption performance of Cu2+-attached PHEMA beads embedded cryogel membranes

For the purification of large molecules, cryogels are an alternative stationary phase to particle based media. But, due to the drawbacks of cryogels (i.e., low surface area) and particle sorbents (i.e., pressure drop in fixed beds), in recent years, the use of hybrid cryogels has greatly increased. In this study, a novel hybrid cryogel column was synthesized for the purification of lysozyme from aqueous solutions and hen egg white (HEW). Firstly, poly(2-hydroxyethyl methacrylate) beads (2 μm size) were prepared, and after iminodiacetic acid (IDA) immobilization, Cu2 + ions were attached via the IDA chelating groups. These arranged Cu2 +-attached PHEMA beads (Cu2 +-ABs) were located into PHEMA based cryogel in order to prepare Cu2 +-ABs embedded supermacroporous hybrid cryogel (Cu2 +-ABsEHC) column. The specific surface area of the hybrid cryogel was found as 95 m2/g by using BET. The amount of IDA on beads was found as 875 μmol IDA/g. It was approached to the optimum adsorption levels at initial lysozyme concentration of 4 mg/mL and pH 8.0 as 874.9 mg/g beads. The purity of lysozyme adsorbed from HEW was studied by SDS-PAGE with a purity of 86.4%. It is demonstrated that this column is a potential separation medium for purification of lysozyme from HEW.