Development of long-lasting antibacterial S-phase based coatings for medical devices

by Dennis Formosa

Institution: University of Birmingham
Department: School of Metallurgy and Materials
Year: 2015
Keywords: RA0421 Public health. Hygiene. Preventive Medicine; TN Mining engineering. Metallurgy
Record ID: 1390407
Full text PDF: http://etheses.bham.ac.uk/5963/


Hospital acquired infections is a modern day reality which plagues health care system around the world. Infections are the cause of 37,000 deaths and a 20 billion euro expense in EU annually. Despite the attention that such infections receive in scientific literature, very few viable solutions have been put forward and implemented. This study systematically developed, characterised and optimized novel long-lasting antibacterial surface coatings for use in medical devices, surgical instruments and hospital equipment. The reactive magnetron-sputtering deposition technique was successfully employed to combine the high mechanical performance of the nitrogen AISI 316 S-phase coating and the antibacterial efficacy of the elements silver and copper. Various configurations including homogeneous monolayers and layered multilayers were investigated for the first time in literature. It was found that substitutional silver and copper atoms can reside within the S-phase lattice while the good corrosion and wear resistance of S-phase are maintained by carefully controlling deposition parameters. Silver was observed to significantly increase the nitrogen uptake up to a previously unreported level of 50at% which has been termed \(ultra-saturation\). Copper based multilayers were found to have a 100% bacteria elimination rate, while silver monolayers also exhibited a good antibacterial efficacy against \(Staphylococcus\) \(aureus\).