Mussel-inspired route to polyethyleneimine decorated MgAl-LDH supported nanosilver hybrid for antimicrobial and catalytic applications

Layered double hydroxides (LDHs) as carriers of antibacterial agents and catalysts have attracted much attention in the research of antibacterial materials. Herein, a novel hybrid of nanosilver-loaded polydopamine (PDA)-polyethylenimine (PEI)-decorated dissected LDH nanosheets (dLDH-PDA-PEI-Ag) was successfully constructed as antibacterial material utilizing a simple mussel-inspired surface engineering strategy. dLDH-PDA-PEI-Ag shows good antimicrobial activities against different bacteria including drug-resistant bacteria, Gram-positive and Gram-negative bacteria. Especially, it has excellent cyclic antibacterial properties against S. epidermidis and E. coli. The bactericidal mechanism of dLDH-PDA-PEI-Ag mainly involves the destruction of cell membrane and production of high level ROS in bacterial cells. In addition, the as-prepared dLDH-PDA-PEI-Ag also presents good catalytic reduction properties for methylene blue and p-nitrophenol in a shorter time. This research indicates that dLDH-PDA-PEI-Ag nanohybrid material has broad application prospects in the fields of public health and environmental protection.