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）：该项目解释了在聚合物基材上加工羟基磷灰石（HA）涂层的新方法，特别是PEEK（聚醚醚酮），以改善组织相容性，增强骨附着和植入物在体内的性能。经过多年的不同类型金属基板涂层经验，一位著名的脊柱外科医生问我们是否可以将HA涂层沉积在用于脊柱植入物的聚合物基板上。考虑到聚合物的熔点通常低于HA的结晶温度，我们的问题是如何在不损坏基材的情况下涂覆聚合物植入物并对涂层进行热处理。我们简要地探索了以下方法：(a)将HA沉积在具有良好涂层结合强度的PEEK上；(b)使用不同的技术对其进行热处理，而不会损坏基材。我们还探索了聚合物和透明质酸涂层之间的中间层在热处理过程中进一步保护基体的作用。我们很高兴地报告，在这个应用程序中，这些努力是成功的，显示了我们的方法的可行性。值得注意的是，我们选择PEEK作为我们的第一个候选者，因为它比其他聚合物具有更高的熔点。我们可以成功地修改PEEK的表面特性，这使我们有信心将这种方法应用于其他聚合物，包括超高分子量聚乙烯。在这项研究中，我们提出在室温下使用离子束辅助沉积（IBAD），然后使用微波技术进行沉积后热处理，在聚合物植入物上制备HA涂层。该技术的优点是：涂层薄而致密，具有较高的抗断裂性，适用于各种生物医学设备和植入物。的结晶度