Chris
Individual bacteria on a Nylon-12 surface.
A team of researchers at the University of Sheffield have successfully 3D printed parts that are resistant to common bacteria.
The study, published today by researchers from the University’s Department of Mechanical Engineering and the School of Clinical Dentistry, combines 3D printing with a silver-based antibacterial compound to produce parts which could potentially stop the spread of infections in hospitals and care homes.
Dr Candice Majewski, lead academic on the project, who works in the Centre for Advanced Additive Manufacturing in the Department of Mechanical Engineering at the University of Sheffield, said: “Managing the spread of harmful bacteria, infection and the increasing resistance to antibiotics is a global concern. Introducing antibacterial protection to products and devices at the point of manufacture could be an essential tool in this fight.
“Most current 3D printed products don’t have additional functionality. Adding antibacterial properties at the manufacturing stage will provide a step-change in our utilisation of the processes’ capabilities.”
Parts with and without the antibacterial additive were submerged in various bacterial solutions to test how many bacteria remained after 24 hours. Parts containing the antibacterial additive were effective against examples of the two main groups of bacteria, Gram positive (Staphylococcus aureus) and Gram negative (Pseudomonas aeruginosa).
Additionally, scientists noted another effect in reducing the number of bacteria stuck to the part surfaces. Bacteria stuck to surfaces form ‘biofilms’ that are often difficult to remove; in this case an anti-biofilm effect was observed, due to bacteria dying before they could stick to the parts. Parts were also found to work less well in liquid containing lots of nutrients and these would interfere with the silver compound.
The research proves that the anti-bacterial compound can be successfully incorporated into existing 3D printing material and when processed under the right conditions, can result in parts with anti-bacterial properties that are non-toxic to human cells.
The research could have wide-reaching potential in areas such as medical devices, parts for hospitals which are subject to high levels of human contact, door handles or children’s toys, oral health products such as dentures and consumer products.
