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

Abstract

Bone infection is one of the most devastating orthopedic outcomes, and overuse of antibiotics may cause drug‐resistance problems. Photothermal therapy(PTT) 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 PTT, this study combines the antibacterial property of Cu to construct a multi‐functional Cu2O@MXene/alpha‐tricalcium phosphate (α‐TCP) scaffold support with internal and external sandwiching through 3D printing technology. On the “outside”, the excellent photothermal property of Ti3C2 MXene is used to carry out the programmed temperature control by the active regulation of 808 nm near‐infrared (NIR) light. On the “inside”, endogenous Cu ions gradually release and the release accumulates within the safe dose range. Specifically, programmed temperature control includes brief PTT 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 PTT, and promoting angiogenesis to improve the repair effect. PTT combined with Cu can deliver a new idea forinfected bone defects through in vitro and vivo application.

Research Progress on Ti3C2Tx-Based Composite Materials in Antibacterial Field

“…These scaffolds support brief PTT to swiftly eliminate early bacteria and periodic low-level photothermal stimulation to stimulate bone tissue growth, thereby minimizing damage to healthy cells and tissues. Meanwhile, endogenous copper ions are gradually released inside the scaffolds within a safe dosage range, enhancing the antibacterial effects of early PTT and promoting angiogenesis, ultimately improving the repair outcomes [ 71 ]. Personalized Ti 3 C 2 T x composite 3D bio-printed hydrogels with rat bone marrow mesenchymal stem cells have both photothermal antibacterial and osteogenic capabilities to accelerate the healing and bone regeneration of rat mandibular defects infected with S. aureus [ 151 ].…”

“…Combining the antibacterial properties of copper, a multifunctional Cu 2 O@Ti 3 C 2 T x /α-tricalcium phosphate scaffold with internal and external sandwiching constructed via 3D printing utilizes the excellent photothermal properties of Ti 3 C 2 T x to control programmed temperature. This includes brief PTT to rapidly eliminate early bacteria and periodic low photothermal stimulation to promote bone tissue growth [ 71 ]. Simultaneously, the slow release of endogenous copper ions strengthens antibacterial efficiency, promotes angiogenesis, and improves the repair effect.…”

Osteogenic Microenvironment Restoration around Dental Implants Induced by an Injectable MXene-Based Hydrogel

“…Therefore, to achieve an ideal therapeutic effect, concentrations of 80 μg/mL MXene and 5 mM MgO were chosen for subsequent experiments based on these considerations. According to the relevant literature 31 and the experimental results above, FMXO was irradiated by 808 nm laser with an intensity of 1 W/cm 2 and maintained at 45 °C for 10 min. Antibiotic Effect of FMXO In Vitro.…”