Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia.
Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, QLD 4059, Australia.
Molecules. 2019 Mar 27;24(7):1201. doi: 10.3390/molecules24071201.
Orthopaedic surgery comes with an inherent risk of bacterial infection, prolonged antibiotic therapy and revision surgery. Recent research has focused on nanostructured surfaces to improve the bactericidal and osseointegrational properties of implants. However, an understanding of the mechanical properties of bactericidal materials is lacking. In this work, the surface properties of hydrothermal TiO₂ nanostructured surfaces are investigated for their effect on bactericidal efficiency and cellular metabolic activity of human osteoblast cells. TiO₂ nanostructures, approximately 307 nm in height and 14 GPa stiffness, were the most effective structures against both gram-positive () and gram-negative () bacteria. Statistical analysis significantly correlated structure height to the death of both bacteria strains. In addition, the surface contact angle and Young's modulus were correlated to osteoblast metabolic activity. Hydrophilic surfaces with a contact angle between 35 and 50° produced the highest cellular metabolic activity rates after 24 hours of incubation. The mechanical tests showed that nanostructures retain their mechanical stability and integrity over a long time-period, reaffirming the surfaces' applicability for implants. This work provides a thorough examination of the surface, mechanical and wettability properties of multifunctional hydrothermally synthesised nanostructured materials, capable of killing bacteria whilst improving osteoblast metabolic rates, leading to improved osseointegration and antibacterial properties of orthopaedic implants.
骨科手术存在细菌感染、长期抗生素治疗和翻修手术的固有风险。最近的研究集中在纳米结构表面，以提高植入物的杀菌和骨整合性能。然而，对于杀菌材料的机械性能缺乏了解。在这项工作中，研究了水热 TiO₂纳米结构表面的表面特性，以研究其对杀菌效率和人成骨细胞细胞代谢活性的影响。TiO₂纳米结构的高度约为 307nm，硬度为 14GPa，是对抗革兰氏阳性菌（）和革兰氏阴性菌（）最有效的结构。统计分析表明，结构高度与两种细菌的死亡显著相关。此外，表面接触角和杨氏模量与成骨细胞代谢活性相关。在孵育 24 小时后，接触角在 35 至 50°之间的亲水表面产生了最高的细胞代谢活性。力学测试表明，纳米结构在很长一段时间内保持其机械稳定性和完整性，再次证实了这些表面在植入物中的适用性。这项工作对多功能水热合成纳米结构材料的表面、力学和润湿性特性进行了全面检查，这些特性能够杀菌同时提高成骨细胞代谢率，从而提高骨科植入物的骨整合和抗菌性能。
