3D Printed Photothermal Scaffold Sandwiching Bacteria Inside And Outside Improves The Infected Microenvironment And Repairs Bone Defects.

Bone infection is one of the most devastating orthopedic outcomes, and overuse of antibiotics maybe cause drug-resistance problems. Photothermal therapy is a promising antibiotic-free strategy for treating infected bone defects. Considering the damage to normal tissues and cells caused by high-temperature conditions in photothermal therapy, this study combines the antibacterial property of Cu to construct a multi-functional Cu 2 O@MXene/alpha-tricalcium phosphate scaffold support with internal and external sandwiching through 3D printing technology. On the "outside", the excellent photothermal property of Ti 3 C 2 MXene is used to carry out the programmed temperature control by the active regulation of 808 nm near-infrared light. On the "inside", endogenous Cu ions gradually release and the release accumulates within the safe dose range. Specifically, programmed temperature control includes brief photothermal therapy to rapidly kill early bacteria and periodic low photothermal stimulation to promote bone tissue growth, which reduces damage to healthy cells and tissues. Meanwhile, Cu ions are gradually released from the scaffold over a long period of time, strengthening the antibacterial effect of early photothermal therapy, and promoting angiogenesis to improve the repair effect. Photothermal therapy combined with Cu can deliver a new idea for long-term prevention of infected bone defects through in vitro and vivo application. This article is protected by copyright. All rights reserved.