Modification of Magnetic Mesoporous Silica Nanoparticles with Antimicrobial Peptide as Recyclable and Durable Antibacterial Agents

Antimicrobial peptides (AMPs) play a significant role in combating antimicrobial resistance. However, the applications of AMPs are constricted by insufficient stability under physiological conditions. Therefore, developing novel and effective antibacterial materials with AMPs is an urgent demand. In this study, magnetic mesoporous silica nanoparticles were fabricated through a facile method and stable modifications of AMPs through the bond formation of Fe-S in the mesopores. The resultant nanoparticles (denoted as Fe3O4@mSiO2@CysHHC10) consisted of Fe3O4 core, SiO2 out layer with cylindrical mesoporous channels, and abundant CysHHC10 immobilized in the mesopores. Fe3O4@mSiO2@CysHHC10 exhibited powerful antibacterial performance against both Gram-negative and Gram-positive bacteria. Also, owing to the CysHHC10 being sheltered with mesoporous channels, Fe3O4@mSiO2@CysHHC10 retained almost more than 99.9% antibacterial efficiency for bacteria throughout nine cycles. Furthermore, the resultant nanoparticles exhibit favorable biocompatibility in vitro. This work provides a novel way for the fabrication of antibacterial magnetic materials with recyclable and durable antibacterial activity.