A Recyclable Magnetic Nanosystem Enable Circulatory Antibacterial Strategy for Static and Dynamic Blood Disinfection

ABSTRACT Bacterial infections in the bloodstream, leading to sepsis, seriously endanger human health. Clinically, blood dialysis is the main treatment, yet is relatively ineffective in handling severe bacterial infections. To better meet the clinical demands for blood disinfection, a biological material with antibacterial, recyclable, and stable features needs to be designed and integrated into the blood dialysis strategy. In this study, we designed a magnetic nanosystem (Fe ₃ O ₄ /CeO ₂ @BP) based on black phosphorus (BP) functionalized with Fe ₃ O ₄ and CeO ₂ to enable a circulatory antibacterial strategy for static and dynamic blood disinfection. The introduction of Fe ₃ O ₄ endowed the nanosystem with sufficient magnetism for rapid recovery prior to circulation reflux. And the coordination between CeO ₂ and BP significantly enhances the ROS generation performance of the nanosystem. In vitro antibacterial experiments demonstrated that the Fe ₃ O ₄ /CeO ₂ @BP nanosystem efficiently and steadfastly inhibited the growth of both Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) over 20 antibacterial cycles. Furthermore, static and dynamic blood tests (simulating venous/arterial flow at two rates) achieved significant antibacterial effects without damaging blood components or physiological indicators. This study exhibits excellent antibacterial performance and reduces potential biosafety risks via complete material recoverability, offering an efficient, safe, and eco‐friendly solution for blood disinfection.