High-capacity dextran-grafted cationic wood monolithic columns for lysozyme extraction from egg whites

As the most widely applied chromatography technique, ion-exchange chromatography has continuously attracted research attention for enhancing performance. Natural green materials, particularly wood, hold promise as novel chromatographic media due to their hierarchical porous structures spanning from millimeters to nanometers. Grafting dextran into the wood surface not only increases the number of active sites but also compensates for low specific surface area of wood. Utilizing sulfonic acid groups as ligands, dextran-grafted strong cation-exchange monolithic wood columns were prepared. With lysozyme as the model protein, the static adsorption capacity and dynamic capacity of the dextran-grafted strong cation-exchange monolithic wood column were measured to be 66.10 mg/g and 40.24 mg/g. Due to mass transfer effects such as chain transport, dextran grafting significantly enhances the adsorption speed of lysozyme. The experimental results indicated that dextran grafting can ameliorate the deficiencies associated with wood as a chromatographic medium, providing data support for the development and large-scale application of wood chromatographic media and suggesting a new direction for high-value utilization of wood. • Grafting dextran onto wood addresses the wood's low specific surface area. • High-performance cation exchange monolithic columns using wood as backbone. • The monolithic columns can efficient separate Lys from egg white. • The monolithic column retained 80 % DBC after 120 adsorption-elution cycles.