Towards Sustainable Green Composite Materials for Medical Implants

我的研究项目的最终目标是改进骨科植入物，随着更年轻、更活跃的人接受关节置换手术，其目前的缺点越来越明显。我的目标是用天然纤维纳米复合材料取代现有的金属植入物，这些金属植入物在相对较短的时间内容易失效，这种材料经过更好的设计，可以模仿真正的人骨的结构和机械性能。这些创新的新材料使用寿命更长，降低了第二次手术的成本和风险，并且将由天然的可再生资源制成。这将带来社会、经济和环境方面的好处：提高患者的生活质量；减少卫生保健系统的压力和成本；以及加拿大生物医学领域的进步，特别强调具有增强性能的绿色产品。

The ultimate goal of my research program is to improve orthopaedic implants, whose current drawbacks are increasingly clear as younger, more active people undergo joint replacement surgery. I aim to replace existing metallic implants, which are prone to failure after a relatively short time, with natural-fibre nanocomposites better engineered to mimic the structural and mechanical properties of real human bone. These innovative new materials will last longer, reducing the costs and risks of a second surgery, and will be made from natural, renewable resources. The benefits will be societal, economic and environmental: increased patient quality of life; reduced pressures and costs on the health care system; and advancement of Canada’s bio-medical sector, with a unique emphasis on a green product with enhanced properties. Total hip and knee replacements are increasing significantly in Canada and elsewhere. Some estimates have forecast a rise of up to 137% in hip and 670% in knee replacements between 2005 and 2030. That would total more than 5 million surgeries a year in the U.S. alone. Current implants generally last only 10 to 15 years, largely because they lack the biological and mechanical characteristics needed to successfully replace human bone. This means the growing number of people who have replacement surgery in middle age are likely to experience implant failure. Roughly 30% of patients in their fifties and 55% of patients under 50 will require a second procedure called revision that is complex and costly, with outcomes less satisfactory than in primary surgery. My research aims to address this huge challenge by developing high-performance nanocomposite materials that are structurally and mechanically closer to human bones. I will achieve this by creating complex hierarchical structures using bone like reinforcing materials (i.e., cellulose fibres and hydroxyapatite) along with biopolymers. Because they will be based on natural cellulosic fibres, and engineered to behave more like bone, these nanocomposite biomaterials will allow for a better bone-implant load transfer and better integration with host tissues. These enhanced properties compared to existing, non-organic materials, will translate into longer-lasting and more effective implants. My proposed research program encompasses numerous innovative aspects. It will create new, high-performance, lightweight, cost-effective nanocomposite biomaterials ready for in-vivo testing. The natural fibres from which they will be made will be grown in Canada. Because these new materials will be environmentally sustainable, they will reduce dependency on non-renewable resources. The proposed research program will help support the translation of this research into real-world orthopaedic applications by involving key Ontario organizations such as MaRS Innovation and St. Michael’s Hospital in clinical (in-vivo) testing and commercialization. This will help Ontario to compete successfully with major global medical device companies. Moreover, because of the sustainability aspect, it will give Canada a special advantage in green medical device technology and its commercialization. The outcomes of this research program will therefore be of lasting strategic value to Canada in two vital sectors: advanced materials and manufacturing, and health care. The proposed research program will also support the formation of HQP in an important and growing area of research. It will train 8 HQPs (5 graduate students and 3 undergraduate students) in much-needed areas by exposing them to applied research and development involving natural fibre-based nanocomposite materials. This creative training will support the continuing transformation of Canada to a knowledge-based economy.