School of Energy and Mechanical Engineering, Jiangxi University of Science and Technology, Nanchang 330013, P. R. China.
Department of Orthopedics, Jiangxi Provincial People's Hospital, The First Affiliated Hospital of Nanchang Medical College, Nanchang 330006, P. R. China.
J Mater Chem B. 2024 Jan 31;12(5):1379-1392. doi: 10.1039/d3tb02600k.
To date, implant-associated infection is still a significant clinical challenge, which cannot be effectively eliminated by single therapies due to the formation of microbial biofilms. Herein, a pH-responsive nanoplatform was constructed the growth of zinc sulfide (ZnS) nanoparticles on the surface of TiC MXene nanosheets, which was subsequently introduced in poly(L-lactic acid) (PLLA) to prepare a composite bone scaffold selective laser sintering technology. In the acidic biofilm microenvironment, the degradation of ZnS released hydrogen sulfide (HS) gas to eliminate the biofilm extracellular DNA (eDNA), thus destroying the compactness of the biofilm. Then, the bacterial biofilm became sensitive to hyperthermia, which could be further destroyed under near-infrared light irradiation due to the excellent photothermal property of MXene, finally achieving gas/photothermal synergistic antibiofilm and efficient sterilization. The results showed that the synergistic gas/photothermal therapy for the composite scaffold not only evidently inhibited the formation of biofilms, but also effectively eradicated the eDNA of the already-formed biofilms and killed 90.4% of and 84.2% of under near infrared light irradiation compared with single gas or photothermal therapy. In addition, the composite scaffold promoted the proliferation and osteogenic differentiation of mouse bone marrow mesenchymal stem cells. Thus, the designed scaffold with excellent biofilm elimination and osteogenesis ability has great potential as an alternative treatment for implant-associated bone infections.
迄今为止，植入物相关感染仍然是一个重大的临床挑战，由于微生物生物膜的形成，单一疗法无法有效消除这种感染。在此，构建了一种 pH 响应型纳米平台，即在 TiC MXene 纳米片表面生长硫化锌（ZnS）纳米粒子，随后将其引入聚（L-乳酸）（PLLA）中，通过选择性激光烧结技术制备复合骨支架。在酸性生物膜微环境中，ZnS 的降解会释放出硫化氢（HS）气体，从而消除生物膜细胞外 DNA（eDNA），从而破坏生物膜的致密性。然后，细菌生物膜对热敏感，由于 MXene 具有优异的光热性能，在近红外光照射下可以进一步被破坏，最终实现气体/光热协同抗生物膜和高效杀菌。结果表明，复合支架的协同气体/光热疗法不仅明显抑制了生物膜的形成，而且还有效地消除了已形成的生物膜中的 eDNA，与单一气体或光热疗法相比，在近红外光照射下，对 和 分别杀灭了 90.4%和 84.2%。此外，该复合支架还促进了小鼠骨髓间充质干细胞的增殖和成骨分化。因此，具有优异的生物膜消除和成骨能力的设计支架有望成为治疗植入物相关骨感染的一种替代方法。
