Metallo--lactamases immobilized by magnetic zeolitic imidazolate frameworks-8 for degradation of -lactam antibiotics in an aqueous environment

Residual antibiotics in nature are an important cause of antimicrobial drug resistance, and how to deal with residual beta-lactam antibiotics in aqueous environments has become an urgent issue. In this work, magnetic zeolitic imidazolate frameworks-8 (ZIF-8) for immobilizing metallo-beta-lactamases (MBLs), or Fe3O4@ZIF-8@MBLs, were successfully synthesized using the one-pot method in aqueous solution. The morphology and chemical structure of Fe3O4@ZIF-8@MBLs were characterized by scanning electron microscopy, energy dispersive spectra, X-ray diffraction, infrared spectra, physical adsorption, and zeta potential. Further, the degradation performance of Fe3O4@ZIF-8@MBLs for beta-lactam antibiotics (penicillin G, cefoperazone, meropenem) in an aqueous environment was investigated by UV-visible absorption spectrophotometry. The results indicated that Fe3O4@ZIF-8@MBLs, compared to control ZIF-8, exhibited superior degradation ability, excellent reusability, and better stability under several harsh conditions. The strategy of combining ZIF-8 and MBLs to form magnetic porous polymers may be suitable for removing beta-lactam antibiotics from an aqueous environment. This work provided an original insight into future studies on the degradation of beta-lactam antibiotics employing MBLs immobilized by magnetic metal-organic frameworks. The strategy of combining metallo-beta-lactamases, zeolitic imidazolate frameworks-8, and magnetic Fe3O4 nanoparticles demonstrates an efficient and reusable composite material to degrade beta-lactam antibiotics in aqueous environments.