Poly(<scp>L</scp>-lactic acid)-BiFeO₃/Ti₃C₂ Scaffolds for Antibacterial Sonodynamic Therapy

Bacterial infection is a severe challenge after artificial transplantation due to the lack of an antibacterial functional implant, which results in delayed healing or even transplant failure. Herein, a sonodynamic antibacterial strategy was proposed by integrating a BiFeO3/Ti3C2 heterojunction into a three-dimensional-printed poly-L-lactic acid scaffold. BiFeO3 can be stimulated using ultrasonic energy to generate carriers. Ti3C2, with good conductivity, can form an interfacial transfer channel with BiFeO3, accelerating interfacial charge transfer. Additionally, forming a Schottky barrier between BiFeO3 and Ti3C2 effectively suppressed electron backflow. The separation of electron–hole pairs was significantly enhanced, thus improving the yield of reactive oxygen species. The results demonstrated that the antibacterial scaffold exhibited antibacterial rates of 93 and 91% against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus exposed to ultrasound, respectively. Additionally, the poly(L-lactic acid)-BiFeO3/Ti3C2 scaffold possessed good biocompatibility and showed great potential for bone regeneration.