Oxygen-vacancy-rich molybdenum carbide MXene nanonetworks for ultrasound-triggered and capturing-enhanced sonocatalytic bacteria eradication

Incurable bacterial infection and intractable multidrug resistance remain critical challenges in public health. A prevalent approach against bacterial infection is phototherapy including photothermal and photodynamic therapy, which is unfortunately limited by low penetration depth of light accompanied with inevitable hyperthermia and phototoxicity damaging healthy tissues. Thus, eco-friendly strategy with biocompatibility and high antimicrobial efficacy against bacteria is urgently desired. Herein, we propose and develop an oxygen-vacancy-rich MoOxin situ on fluorine-free Mo2C MXene with unique neural-network-like structure, namely MoOx@Mo2C nanonetworks, in which their desirable antibacterial effectiveness originates from bacteria-capturing ability and robust reactive oxygen species (ROS) generation under precise ultrasound (US) irradiation. The high-performance, broad-spectrum microbicidal activity of MoOx@Mo2C nanonetworks without damaging normal tissues is validated based on systematic in vitro and in vivo assessments. Additionally, RNA sequencing analysis illuminates that the underlying bactericidal mechanism is attributed to the chaotic homeostasis and disruptive peptide metabolisms on bacteria instigated by MoOx@Mo2C nanonetworks under US stimulation. Considering antibacterial efficiency and a high degree of biosafety, we envision that the MoOx@Mo2C nanonetworks can serve as a distinct antimicrobial nanosystem to fight against diverse pathogenic bacteria, especially eradicating multidrug-resistant bacteria-induced deep tissue infection.