Durable and Washable Composite Material from Antibacterial Copper Nanoparticles
Unique copper-coated uniforms would soon be worn by healthcare professionals, doctors, and nurses in an effort to reduce infection outbreaks at hospitals. These uniforms are especially brushed with very small copper nanoparticles to minimize the spread of viruses and bacterial infections, for example, Escherichia coli (E. coli), at hospitals.
In association with universities in China, material scientists at The University of Manchester, have developed a ‘durable and washable, concrete-like’ composite material, which is fabricated from antibacterial copper nanoparticles. The team also came up with a novel way to bind the composite to wearable materials, for example, polyester and cotton, which has been a challenging aspect for researchers before.
A major problem in hospitals throughout the UK, bacterial infections have been rising due to their spread on clothing and surfaces. In fact, over 5,500 NHS patients have died from E. coli infections alone in 2015. According to Government estimates, the cost of these bacterial infections to the NHS comes to £2.3 billion for the current year alone.
Gold and silver are precious metals that possess excellent antimicrobial and antibacterial properties but due to their extremely high costs, their commercial use in textile production is prohibitive. Therefore, copper became the preferred material for scientists because this material has very similar antibacterial properties to silver and gold and ate the same time it is also considerably cheaper. This is the reason why material chemists are devoting their attention to investigating the potential of using copper as the vital antimicrobial agent.
Conversely, before this breakthrough was made, there were certain limitations regarding the methods for binding copper to materials, such as cotton, for antimicrobial and medical textile production. Now, with the help of a process known as ‘Polymer Surface Grafting’, the researchers have adhered copper nanoparticles to polyester and cotton by means of a polymer brush, producing a powerful chemical bond.
According to the researchers, it is this bond which has resulted in exceptional durability and washable properties. These advancements may ultimately witness copper-covered textiles and uniforms commercialized in the near future.
Lead author, Dr. Xuqing Liu, from the School of Materials, said: “Now that our composite materials present excellent antibacterial properties and durability, it has huge potential for modern medical and healthcare applications.”
The team tested its copper nanoparticles on cotton, as this material is used more extensively than any other natural fiber, and polyester as it is a characteristic polymeric, manmade material. Small copper nanoparticles measuring between 1 and 100 nanometers (nm) were brushed on each material. 100 nm is the equivalent to merely 0.0001 millimeters (mm).
The researchers observed that their copper-coated cotton and polyester fabrics exhibited excellent antibacterial resistance against E. coli and Staphylococcus aureus (S. aureus), even after when they were repeatedly washed for 30 times. The polymer brush technique developed at the University is much more effective when compared to the conventional process of copper coating
Dr. Liu said: “These results are very positive and some companies are already showing interest in developing this technology. We hope we can commercialize the advanced technology within a couple of years. We have now started to work on reducing cost and making the process even simpler.”