A goal of current orthopedic biomaterials research is to design implants that induce controlled and guided growth of tissue, and rapid healing. To achieve these goals a better understanding of events at the bone-material interface is needed, as well as the development of new materials and approaches that promote osseointegration. Profs. Popat and Grimes propose the use of well controlled nanostructured titania interfaces to enhance implant osseointegration. The integration of controlled nanoscale titania architectures into existing implant materials can promote osteoblast differentiation and matrix production, and enhance short- and long-term osseointegration. Moreover, the ability to create model nanodimensional constructs that mimic physiological systems can aid in studying complex tissue interactions in terms of cell communication, response to matrix geometry, and effect of external chemical stimuli. The fabrication routes developed by the group of Prof. Grimes in collaboration with Prof. Popat are flexible and cost-effective, enabling realization of desired topologies and chemistries on existing bulk implant materials with sufficient stability and strength. Such control over the nanoscale interface can prove advantageous for a broad range of biomaterial applications. Since the reality of creating a new biomaterial technology is predicated upon achieving affordable, biocompatible and durable materials that are able to withstand complex physiological environments, the intellectual merit of this project is to integrate nanotechnology with biology by: (a) Developing technologies that can be easily adopted to exiting technologies in market; and (b) Understanding what influences and controls bone-material interfaces. A further Broader Impact of the work is the training of next generation of scientists and engineers, and providing outreach-oriented laboratory internships for undergraduates and underrepresented students in science/engineering to work in this vitally important interdisciplinary field.
A goal of current orthopedic biomaterials research is to design implants that induce controlled, guided, and rapid healing. To achieve these goals a better understanding of events at the bone-material interface is needed, as well as the development of new materials and approaches that promote osseointegration. We propose the use of well controlled nanostructured titania interfaces to enhance implant osseointegration. The integration of controlled nanoscale titania architectures into existing implant materials can promote osteoblast differentiation and matrix production, and enhance short-term and long-term osseointegration. Moreover, the ability to create model nanodimensional contructs that mimic physiological systems can aid in studying complex tissue interactions in terms of cell communication, response to matrix geometry, and effect of external chemical stimuli. By understanding how physical surface parameters at the nanoscale influence cellular adhesion and differentiation, we can more effectively design biomaterial interfaces. The fabrication routes of these titania nano-architectures are flexible and cost-effective, enabling realization of desired topologies and chemistries on existing bulk implant materials with sufficient stability and strength. Such control over the nanoscale interface can prove advantageous for a broad range of biomaterial applications. Since the reality of a creating new biomaterial technology is predicated upon achieving affordable, biocompatible, durable materials that are able to withstand complex physiological environments, the Broader Impacts of our project are to be considered with respect to the cost and ease of application of new implant materials and architectures, understanding what influences and controls bone- material interfaces, and training of the next generation of scientists and engineers to work in this vitally important interdisciplinary field. The development and application of nanostructured platforms based on novel titania nanotube arrays provides insight into cell-material interactions for the development of improved orthopedic and transcutaneous implant surfaces. It is envisioned that the incorporation of such nanoarchitectures on micro-porous metals will further facilitate the culture and maintenance of differentiated cell states, and provide long-term cell viability and functionality. It is anticipated that these nanotube arrays will be able to mimic the complex geometries of natural tissue and will provide a porous mesh for the growth and maintenance of the cells. We believe that molecular and cellular assessment of in vitro and in vivo responses to implant surface topography will contribute to the improved engineering of implants. The thrombogenic effects of titania nanotube arrays have been evaluated for their use as interfaces in blood-contacting implants. The ability to modulate the thrombogenicity of titanium surfaces may prove beneficial towards the long-term success of these implantable devices. The findings of this study show a decrease in thrombogenic effects on titania nanotube arrays as compared to biomedical grade titanium. These results suggest improved blood-compatibility of titania nanotube arrays, identifying this nanoarchitecture as a potential interface for promoting the long-term success of blood-contacting implants. There are three major educational themes within the program: 1) high quality, interdisciplinary graduate education, 2) laboratory summer internships for visiting high school students and undergraduates, and 3) outreach efforts aimed at high school level students. It is a major objective of the PI to expose the participating graduate students to all of the multiple research facets of the program. The program supported four undergraduate students (one woman, one veteran, one minority), one high school teacher over summer (minority) and one graduate student (woman).
