Processing and Characterization of Coatings for Polymeric Implants

聚合物植入物涂层的加工和表征

• 批准号: 8477170
• 负责人: Afsaneh Rabiei
• 金额: $ 17.59万
• 依托单位: NORTH CAROLINA STATE UNIVERSITY RALEIGH
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8477170
• 关键词: Address; Adhesions; Alloys; Animals; Area; Biocompatible Coated Materials; Cell Culture Techniques; Cereals; Chemicals; Clinical; Controlled Study; Crystallization; Dentistry; Deposition; Development; Devices; Electron Microscope; Film; Fracture; Goals; HA coating; Hardness; Heating; Histocompatibility; Hydroxyapatites; Implant; In Vitro; Ions; Lasers; Lead; Mechanics; Metals; Methods; Modeling; Operative Surgical Procedures; Optics; Orthopedics; Oryctolagus cuniculus; Performance; Polymers; Process; Property; Reporting; Resistance; Safety; Scanning; Sorting - Cell Movement; Surface; Surface Properties; Surgeon; Techniques; Technology; Temperature; Testing; Thick; Time; Tissues; Vertebral column; Work; Zirconium; biomaterial compatibility; bone; experience; implant coating; implantable device; improved; in vivo; innovation; interfacial; melting; microwave electromagnetic radiation; next generation; novel; novel strategies; polyetheretherketone; process optimization; research study; response; sample fixation; ultra-high molecular weight polyethylene; zirconium oxide

DESCRIPTION (provided by applicant): This project explains a new approach towards processing Hydroxyapatite (HA) coating on polymeric substrates in general and PEEK (polyetheretherketone) in particular to improve tissue compatibility, enhance bone apposition and performance of the implant in the body. After many years of experience with coating various types of metallic substrates, we were asked by a well-known spine surgeon if we can deposit an HA coating on a polymeric substrates for application in spine implants. The question for us was how to coat a polymeric implant and heat treat the coating without damaging the substrate, considering the fact that the melting point of polymers is normally lower than the crystallization temperature of HA. We briefly explored methods to (a) deposit HA on PEEK with good bonding strength of the coating and (b) heat-treat it using different techniques without damaging the substrate. We have also explored the effect of an intermediate layer between the polymer and HA coating to further protect the substrate during the heat-treatment. We are pleased to report in this application that these efforts were successful in showing the feasibility of our approach. t is notable that we selected PEEK as our first candidate because it has a higher melting point compared to other polymers. Confirmation that we can successfully modify the surface properties of PEEK has given us confidence that we can adapt this approach to other polymers, including ultra-high molecular weight polyethylene. In this study we propose to produce the HA coating on polymeric implants using an Ion Beam Assisted Deposition (IBAD) at room temperature followed by a post deposition heat-treatment using microwave technique. The advantages of the proposed technology are: The coating is a thin and dense layer with high fracture resistance suitable for all sorts of biomedical devices and implants. The crystallinity of the coating can be controlled precisely through the novel heat treatment approach (proposed in this study). The microwave and laser techniques allow the heat to be focused in a small thickness of the film without any damage to the polymeric substrate. At the same time, depositing the coating at room temperature will eliminate any potential thermal degradation of the polymeric implant. The chemical composition of the coating can be precisely controlled. The presence of the thermal barrier coating layer between the HA and substrate will further protect the substrate from any excessive heat and thermal degradation. It will also help the nucleation of HA crystals during heat-treatment expediting the process. Both early and long-term bone responses will be assessed in a rabbit model. The proposed study investigates a new technique for coating polymeric devices that can have a great impact on the development of the next generation of polymeric implants and a significant innovation in biomedical coating technology. It has the potential to dramatically enhance the feasibility of using low-modulus polymers in applications that were previously considered impractical because of concerns over the poor tissue integration of uncoated materials.

描述（由申请人提供）：该项目解释了一种在聚合物底物上处理羟基磷灰石（HA）涂层的新方法，尤其是PEEK（聚醚酮），以改善组织兼容性，增强体内植入物的骨骼含量和性能。经过多年在涂层各种类型的金属底物经验的经验之后，我们被一位知名的脊柱外科医生询问我们是否可以将HA涂层沉积在聚合物基板上，以在脊柱植入物中施用。对我们来说，问题是如何涂抹聚合物植入物并进行热处理涂层而不会损坏底物，这是因为聚合物的熔点通常低于HA的结晶温度。我们简要探索了（a）涂层的良好粘结强度和（b）使用不同技术的热处理的方法（a）沉积的方法，而不会损坏基板。我们还探索了聚合物和HA涂层之间中间层的影响，以进一步保护热处理期间的底物。我们很高兴在此应用程序中报告说，这些努力成功地展示了我们的方法的可行性。 T值得注意的是，我们选择了PEEK作为我们的第一个候选人，因为它与其他聚合物相比具有更高的熔点。确认我们可以成功地修改PEEK的表面特性使我们相信我们可以将这种方法适应其他聚合物，包括超高分子量聚乙烯。在这项研究中，我们建议在室温下使用离子束辅助沉积（IBAD）在聚合物植入物上产生HA涂层，然后使用微波技术进行沉积后热处理。所提出的技术的优点是：涂层是薄而致密的层，具有高断裂性的耐药性，适合各种生物医学设备和植入物。结晶度 涂层可以通过新型的热处理方法（在本研究中提出）来精确控制。微波和激光技术使热量可以聚焦在膜的较小厚度中，而不会损坏聚合物基板。同时，在室温下沉积涂层将消除聚合物植入物的任何潜在热降解。涂层的化学成分可以精确控制。 HA和底物之间的热屏障涂层的存在将进一步保护底物免受任何过多的热和热降解。在热处理期间，它还将有助于HA晶体的成核加速过程。早期和长期骨反应都将在兔模型中进行评估。拟议的研究调查了一种针对涂料聚合物设备的新技术，该技术可能会对下一代聚合物植入物的发展产生重大影响，并在生物医学涂料技术中产生重大创新。它有可能显着提高在以前被认为是不切实际的应用中使用低模块化聚合物的可行性，因为人们担心未涂层材料的组织整合不良。