Project description
High-performance silver doped carbon coatings for biomedical applications
Diamond-like carbon (DLC) films present exceptional mechanical properties that make them ideal as protective coatings. Due to their high hardness, low friction, and biocompatibility with living cells, silver-doped DLC coatings are highly valued in the biomedical field. Increased amounts of silver in the coating have shown to improve its biocompatibility, but excessive amounts could reduce its mechanical strength and durability and prove to be toxic to humans. The EU-funded HePULSE project plans to synthesise DLC coatings with a precise amount of silver nanoparticles at specific locations in the coating. The silver nanoparticles will be created in situ by rapid plasma quenching and simultaneously embedded in the DLC matrix in a single-step process.
Objective
Diamond-like carbon (DLC) coatings are renowned for their excellent mechanical properties and biocompatibility. The overall DLC market is projected a compound annual growth rate (CAGR) of 14% by 2020, while the DLC in biomedical sector alone is growing with a CAGR of 33%, which is inspiring advanced DLC research for biomedical use. Hard DLC coatings have poor toughness which limits their application for joint implants that involve impact, shear, and torsion. Silver-doped DLC coatings (Ag-DLC) are increasing in popularity in the biomedical sector as they boost biocompatibility and toughness of pure DLC coatings simultaneously. The biocompatibility of Ag-DLC is shown to increase by increasing Ag fraction, but excessive Ag reduces the mechanical strength and durability and a high Ag dose may become toxic to the patient if the coating fails. We have identified that Ag is essential for early post-surgery, thus it would be highly beneficial to develop a coating where Ag is only doped near the surface, providing maximum biological performance without reducing DLC strength. In fact, selective Ag doping in a DLC matrix is challenging through established physical vapour deposition techniques.
In this project, we are aiming to develop a novel DLC coating with precise and localized doping of Ag nanoparticles using the sputtering method. The Ag nanoparticles will be created in-situ by rapid plasma quenching with He pulses and simultaneously embedded in the DLC matrix in a single-step process. The unique features are precise amounts and specific size of Ag nanoparticles which will be embedded at controlled depths in the DLC matrix. The coatings will be tested for biological functioning i.e. biocompatibility and antimicrobial tests and mechanical performance, which includes hardness, toughness, and tribology. The new Ag-DLC coatings are expected to present a simultaneous improvement in biological and mechanical performance due to their unique tailor-made architecture.
Fields of science
- natural scienceschemical sciencesinorganic chemistrynoble gases
- natural scienceschemical sciencesinorganic chemistrytransition metals
- engineering and technologymaterials engineeringcoating and films
- engineering and technologynanotechnologynano-materials
- engineering and technologymechanical engineeringtribology
Keywords
Programme(s)
Funding Scheme
MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF)Coordinator
NE1 8ST Newcastle Upon Tyne
United Kingdom