Biomaterials (nanomaterials, bioadhesives, tissue engineering, and more).
Hao Fong and Todd Menkhaus:
The Materials-processing Technique of Electrospinning and Biomedical Applications of Electrospun Polymer, Ceramic, Carbon/Graphite, Metallic, Composite, and Hierarchically-structured Nanofibers and/or Nanofibrous Materials
The interested/studied applications include, but are not limited to:
- Bioseparation of biopharmaceutical therapeutics such as proteins,
- Immobilization of biomacromolecules such as enzymes,
- Bio-sensors and bio-detectors,
- Polymeric dental restorative composites,
- Controllable/targeted drug delivery,
- Antimicrobial wound dressing,
- Tissue Engineering.
Grant A. Crawford:
Advanced Materials for Biomedical Application
Research in the Crawford lab generally involves studying the relationship between processing, microstructure, and biological performance of advanced biomaterials. The Crawford lab currently develops advanced biomedical materials by means of advanced manufacturing (laser powder deposition and cold spray technology) and electrochemical techniques. Current research includes:
- Hierarchical TiO2 Nanotube Coatings
Titanium (Ti) and Ti alloys have been used extensively as bone implant materials due to their high strength-to-weight ratio, good biocompatibility, and excellent corrosion resistance. Titanium, however, is bioinert and osseointegration via the natural oxide is a long process. Over the last 30 years, a variety of surface modification techniques have been developed in an effort to reduce the time needed for osseointegration and limit the formation of fibrous tissue, thereby improving implant lifetime. While these developments have certainly improved implant performance, there is an increasing need for higher performance implants due to increasing human life-expectancy and increasing activity of patients with medical implants.
This project focuses on fabricating bioactive TiO2 nanotube coatings consisting of micro-scale patterns on the microscale and TiO2 nanotubes on the nanoscale. The hierarchical structure is processed via advanced manufacturing techniques such as laser powder deposition and cold spray technology in conjunction with electrochemical techniques. This study examines the relationship between processing conditions, the micro/nanostructure of the hierarchical coating, and the coating performance (e.g. in vitro/in vivo biological response, wetting behavior, coating adhesion, corrosion resistance).
- Functionally Graded Bio-composite Cold Spray Coatings
Hydroxyapatite (HAP), Ca10(PO4)6(OH)2, is a well-known bio-ceramic commonly used in biomaterial applications due to its similarity to human bone. As such, HAP coatings are commonly applied to titanium implants in an effort to improve the bioactivity of the titanium surface. The most common technique for applying HAP coatings to titanium (as well as other implant materials) is plasma spray deposition. There are two major disadvantages to this technique: 1) poor coating adhesion and, 2) high deposition temperature.
To overcome the limitations discussed above, this research focuses on development of bioactive functionally graded HAP/Ti composite coatings deposited via cold spray technology. Cold spray technology is a solid state deposition process whereby small (~1-50um) particles are introduced into a high velocity gas stream and accelerated (~300-1200 m/s) onto a substrate where they then deform developing into a coating. This project studies the relationship between processing conditions, coating microstructure, and coating performance (e.g. in vitro/in vivo biological response, coating adhesion strength).
- Novel “Super Hard” Ceramics for Biomedical Application
There are a variety of load bearing wear surfaces found in orthopedic implants today. In fact, many knee and hip implant failures can be attributed to wear related failures. Naturally, there is a significant interest in wear resistant materials that can be used in load bearing implants. With this in mind, this research studies a novel “Super Hard” ceramic material for use in load bearing implant applications. This novel material is one of the hardest materials on earth and also has a low density (ideal for implants) and low coefficient of friction (ideal for wear applications). This work focuses on characterizing (cytotoxicity, biocompatibility, wear behavior, corrosion behavior, etc) this novel ceramic material for use in the body.
- Anti-microbial Copper by Cold Spray Technology
Copper is a well-known anti-microbial metal. Copper, however, is relatively expensive and the mechanical properties are not ideal for all applications. This project focuses on studying the fabrication of antimicrobial copper coatings on varies substrates using cold spray technology. Furthermore, we are interested in studying the impact of cold spray deposition parameters and resulting microstructure on final antimicrobial performance. Finally, this project also involves the antimicrobial performance of various corrosion products on copper to assess the long-term care and viability of antimicrobial copper surfaces.