Sticking-bacteria gel enhancing anti-multidrug-resistant microbial therapy under ultrasound

The use of antibiotic could cause severe drug-resistance and the increasing spread of pathogenic drug-resistant bacteria has brought a big threat to human health, hence, some innovative methods inspired, such as sonodynamic therapy, have become increasingly attractive for realizing the antibiotic-free methods against bacterial infection. However, many pathogens can invade normal healthy cells to establish intracellular replicative niches, which makes it more difficult to kill and remove these bacteria. Herein, inspired by respiratory mucus trapping bacteria to kill them, we developed a novel gel of amorphous TiO_x nanofibers dotted with Ti₂C(OH)₂ nanosheets, which could capture and trap bacteria into the gel via a strong binding ability toward bacteria by forming a Ti–O–P bond between phosphate in the bacterial wall and Ti-OH in the gel, thereby, efficiently blocking the invasions of bacteria. Also, the gel has excellent ability for generating reactive oxygen species (ROS) under ultrasound irradiation, therefore, the bacteria in the gel could be effectively killed by the ROS produced under ultrasound irradiation. Moreover, Ti₂C(OH)₂ in the gel was able to scavenge H₂O₂, and transfer it into O₂ in the infection environment, providing enough O₂ for sonodynamic therapy. The experimental results have demonstrated that the functional gel obviously accelerated the healing of multidrug-resistant microorganisms-infected wounds.