Abstract
The widespread use of antibiotics has led to their continuous release into aquatic environments, creating significant environmental and public health concerns. In this study, magnetic metal–organic framework nanocomposites (mZIF-8) were developed as multifunctional materials enabling simultaneous adsorption and enzymatic degradation of penicillin (PEN). Fe3O4 nanoparticles coated with arabinogalactan were incorporated into ZIF-8 to allow magnetic recovery, while ß-lactamase was covalently immobilized using glutaraldehyde (GA). The immobilization process was optimized by varying GA concentration, with the highest residual enzyme activity (59%) and immobilization efficiency (90%) obtained at 5% (v/v) GA. The ß-lactamase@mZIF-8 system exhibited a dual removal mechanism combining rapid adsorption and catalytic degradation. At 0.1 mg/mL PEN, nearly complete removal was achieved within 40 min, primarily driven by adsorption. At 1 mg/mL, adsorption remained dominant but enzymatic catalysis accelerated removal kinetics. At 10 mg/mL, adsorption capacity became saturated, while immobilized ß-lactamase enabled continued degradation, reducing PEN concentration to 6% after 192 h. These results demonstrate that enzyme immobilization on magnetic ZIF-8 significantly enhances pollutant removal efficiency and extends the operational range of adsorption-based systems for antibiotic remediation.
