Faculty of Science, Department of Biology, University of Zagreb, 10000 Zagreb, Croatia.
Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Ivana Lučića 5, 10000 Zagreb, Croatia.
J Hazard Mater. 2023 Sep 15;458:131867. doi: 10.1016/j.jhazmat.2023.131867. Epub 2023 Jun 15.
Bacteria Acinetobacter baumannii is a persistent issue in hospital-acquired infections due to its fast and potent development of multi-drug resistance. To address this urgent challenge, a novel biomaterial using silver (Ag) ions within the hydroxyapatite (HAp) lattice has been developed to prevent infections in orthopedic surgery and bone regeneration applications without relying on antibiotics. The aim of the study was to examine the antibacterial activity of mono-substituted HAp with Ag ions and a mixture of mono-substituted HAps with Sr, Zn, Mg, SeO and Ag ions against the A. baumannii. The samples were prepared in the form of powder and disc and analyzed by disc diffusion, broth microdilution method, and scanning electron microscopy. The results from the disc-diffusion method have shown a strong antibacterial efficacy of the Ag-substituted and mixture of mono-substituted HAps (Sr, Zn, Se, Mg, Ag) toward several clinical isolates. The Minimal Inhibitory Concentrations for the powdered HAp samples ranged from 32 to 42 mg/L (Ag substituted) and 83-167 mg/L (mixture of mono-substituted), while the Minimal Bactericidal Concentrations after 24 h of contact ranged from 62.5 (Ag) to 187.5-292 mg/L (ion mixture). The lower substitution level of Ag ions in a mixture of mono-substituted HAps was the cause of lower antibacterial effects measured in suspension. However, the inhibition zones and bacterial adhesion on the biomaterial surface were comparable. Overall, the clinical isolates of A. baumannii were effectively inhibited by substituted HAp samples, probably in the same amount as by other commercially available silver-doped materials, and such materials may provide a promising alternative or supplementation to antibiotic treatment in the prevention of infections associated with bone regeneration. The antibacterial activity of prepared samples toward A. baumannii was time-dependent and should be considered in potential applications.
鲍曼不动杆菌是医院获得性感染中的一个持续问题，因为它对抗生素的快速和强大的多药耐药性发展。为了解决这一紧迫挑战，开发了一种新型生物材料，在羟基磷灰石（HAp）晶格中使用银（Ag）离子，以防止骨科手术和骨再生应用中的感染，而不依赖抗生素。该研究的目的是检查单取代的 HAp 与 Ag 离子和单取代的 HAp 与 Sr、Zn、Mg、SeO 和 Ag 离子的混合物对 A.baumannii 的抗菌活性。样品以粉末和圆盘的形式制备，并通过圆盘扩散、肉汤微量稀释法和扫描电子显微镜进行分析。圆盘扩散法的结果表明，Ag 取代和单取代 HAp（Sr、Zn、Se、Mg、Ag）混合物对几种临床分离株具有很强的抗菌效果。粉末 HAp 样品的最小抑菌浓度范围为 32-42mg/L（Ag 取代）和 83-167mg/L（单取代混合物），而接触 24 小时后的最小杀菌浓度范围为 62.5（Ag）至 187.5-292mg/L（离子混合物）。在单取代 HAp 混合物中，Ag 离子的低取代水平是悬浮液中测量的抗菌效果较低的原因。然而，生物材料表面的抑菌圈和细菌黏附是相当的。总的来说，取代的 HAp 样品有效地抑制了 A.baumannii 的临床分离株，其抑制效果可能与其他市售的载银材料相同，并且这些材料可能为预防与骨再生相关的感染提供一种有前途的替代或补充抗生素治疗的方法。制备样品对 A.baumannii 的抗菌活性是时间依赖性的，在潜在应用中应予以考虑。
