Study on the adsorption properties of lysozyme by cellulose microspheres modified with reactive red 120

Microspheres of cellulose acetate, characterized by a multi-layered, uniform, and continuous porous structure, were synthesized through the process of emulsion evaporation. Subsequent deacetylation facilitated the modification of the cellulose microspheres’ surface, which was functionalized with Reactive Red 120, serving as an affinity dye ligand. This modification yielded a cationic adsorbent. The adsorptive behavior of lysozyme from aqueous solutions, with lysozyme designated as the target protein, was examined in relation to the effects of pH and ionic strength. The adsorptive capacity of the cellulose microspheres, modified with Reactive Red 120, for lysozyme was determined to be 106.57 mg g⁻¹, exhibiting rapid equilibration within 40 min. The adsorption kinetics and thermodynamics were accurately described by the pseudo-second-order kinetic model and the Langmuir model, respectively, with correlation coefficients (R²) of 0.98 and 0.97. Furthermore, dynamic adsorption experiments revealed an enhanced adsorption capacity of 36.5 mg g⁻¹, significantly surpassing that of the unmodified microspheres. The cellulose microspheres, derived from cellulose acetate and modified accordingly, are environmentally benign and sustainable, thereby holding significant promise for various biological applications.