Super-antibacterial Ti surfaces via pulse laser 3D patterning of Ag followed by catalytic ceramic conversion

控制微生物的传播是生物医学应用的一个关键问题。细菌和其他病原体在表面的存在会导致有害的生物效应，如感染或植入失败，因此污染控制是至关重要的。常见的灭菌技术包括消毒剂和高强度光，但这些过程持续时间有限，再次暴露在环境中会重新引入污染物。此外，反复使用灭菌技术可能对健康产生有害影响，因此固有的抗菌特性是理想的，材料的表面图案已被证明在抵抗细菌粘附和生物膜形成方面是有效的，此外，离子的植入，如银，已经建立了抗菌作用的先例。在这个博士项目中，将设计和创造用于生物医学应用的新型超抗菌钛表面。为此，将使用脉冲激光打印将3D图案化Ag沉积在钛表面，然后使用先进的催化陶瓷转化，将表面图案化和抗菌材料掺杂结合起来，生成新型的Ag掺杂3D图案化TiO2。此外，图案化类金刚石（DLC）沉积和性能在不同的衬底将被检查。DLC具有良好的生物相容性，同时具有高硬度和低摩擦系数，广泛应用于生物医学领域；表面DLC既能在植入物上帮助组织形成，又能防止离子从金属基质上释放。DLC涂层也提供了机会，通过使用在注射成型插入抗菌模式的模板。此外，DLC涂层减少了反对模具填充的摩擦以及脱模所需的力，因此提高了零件生产的性能，并增加了模具寿命。飞秒激光加工有助于精确形成纹理表面，因此，激光诱导周期性表面结构（LIPSS）将在DLC上产生抗菌效果；然后可以转移到注塑塑料上的图案，例如用于正畸的那些。如有必要，将研究氮氧三束（激光、离子和电子）表面选择性合金化以进一步提高性能。三维层结构、微观结构和界面将使用三束设备、原子力显微镜、XPS、拉曼光谱、扫描电镜和透射电镜进行全面研究。机械性能将使用环境纳米压痕平台进行探测，功能图案表面的耐久性将通过电化学和摩擦学测试进行评估。所涉及的机制将被调查，以促进科学认识。

Control of microorganism spread is a key concern for biomedical applications. The presence of bacteria and other pathogens on surfaces can lead to detrimental biological effects, such as infection or implant failure, hence contamination control is vital. Common sterilisation techniques include disinfectants, and high intensity light, however these processes have limited duration and re-exposure to environments will reintroduce contaminants. Furthermore, repeated use of sterilisation techniques may have deleterious health effects, therefore inherent antibacterial properties are desirable Surface patterning of materials has been evidenced to be effective in resisting bacterial adhesion and biofilm formation, furthermore implantation of ions, such as silver, has established precedent for antimicrobial action. Within this PhD project, novel super-antibacterial Ti surfaces for biomedical applications will be designed and created. To this end, 3D patterned Ag will be deposited on titanium surfaces using pulse laser printing followed by advanced catalytic ceramic conversion to generate innovative 3D patterned TiO2 doped with Ag, combining both surface patterning and antibacterial material doping. Furthermore, patterned diamond-like carbon (DLC) deposition and properties on varied substrates will be examined. DLC presents excellent biocompatibility in conjunction with high hardness and low coefficients of friction, making it widely applicable for biomedical applications; surface DLC can act to both aid tissue formation on implants, and to prevent ion release from metallic substrates. DLC coatings also present opportunity for templating of antibacterial patterns through use in injection moulding inserts. Moreover, DLC coatings reduce the friction which opposes mould infilling as well as the forces required for demoulding, therefore improving performance of part production, and increasing mould lives. Femtosecond laser processing facilitates precise formation of textured surfaces, hence, laser-induced periodic surface structures (LIPSS) will be produced on DLC for antibacterial efficacy; patterns which may then be transferred onto injection moulded plastics, such as those used in orthodontics. If necessary, tri-beam (laser, ion, and electron) surface selective alloying with N and O will be investigated for further property enhancement. The 3D layer structures, microstructures and interfaces will be fully studied using the tri-beam facility, AFM, XPS, Raman spectroscopy, SEM, and TEM. The mechanical properties will be probed using an environmental nano-indentation platform, and the durability of the functionally patterned surfaces will be evaluated through electrochemical and tribological testing. The mechanisms involved will be investigated to advance scientific understanding.