A new copper product can kill bacteria faster and more effectively than standard copper, improve the efficiency by more than 100 times, and help fight the growing threat of superbacteria.

Copper is magnified 2000 times under scanning electron microscope, showing its unique micro comb structure.

The new copper product is the result of a collaborative study between RMIT University and CSIRO, the Australian National Science Institution, which has just been published on biomaterials.

Copper has long been used against different bacterial strains, including the common Staphylococcus aureus, because ions released from metal surfaces are toxic to bacterial cells.

But as Ma Qian, a distinguished professor at RMIT University, explained, when using standard copper, the process is slow, and researchers around the world are trying to speed up the process.

A standard copper surface kills about 97% of Staphylococcus aureus in four hours.

Incredibly, when Staphylococcus aureus was placed on our specially designed copper surface, it destroyed more than 99.99% of the cells in just two minutes. It is not only more effective, but also 120 times faster.

These results were obtained without any drug help. Copper structures have proven themselves very effective for this common material.

The team believes that once further developed, this new material may have a wide range of applications, including antibacterial door handles and other touch surfaces in schools, hospitals, families and public transport, as well as filters in antibacterial respirators or ventilation systems, and masks.

The team is now studying the effectiveness of enhanced copper on sars-cov-2, including evaluating 3D printed samples.

Other studies have shown that copper may be very effective against viruses, leading the U.S. Environmental Protection Agency to officially approve copper surfaces for antiviral purposes earlier this year.

Lead author Dr. Jackson Lee Smith said that the unique porous structure of copper is the key to its effectiveness as a rapid bacterial killer.

The alloy is made by special copper mold casting process, and the copper and manganese atoms are arranged into a specific structure.

Then, a cheap and scalable chemical process called "dealloying" is used to remove manganese atoms from the alloy, leaving tiny micron and nano cavities on the surface of pure copper.

Copper is composed of comb like micropores, and each tooth of the comb like structure has smaller nano pores; It has a huge active surface area. The pattern also makes the surface super hydrophilic or hydrophilic, so water exists on it in the form of flat film rather than droplets.

Hydrophilicity means that bacterial cells are difficult to maintain their shape when stretched by surface nanostructures, while porous patterns allow copper ions to be released faster.

These comprehensive effects will not only lead to the structural degradation of bacterial cells, making them more vulnerable to toxic copper ions, but also promote the absorption of copper ions by bacterial cells. It is this combination of effects that greatly accelerates the elimination of bacteria.

Researchers around the world are seeking to develop new medical materials and equipment to help reduce the increase of antibiotic resistant superbacteria by reducing the demand for antibiotics. Drug resistant infections are on the rise. With the limited new antibiotics on the market, the development of antibacterial materials may play an important role in helping to solve this problem.

This new copper product provides a promising and affordable option against superbacteria, which is just an example of CSIRO's help in addressing the growing risk of antibiotic resistance.

The study was initiated through the rmit-csiro PhD project and subsequently co funded by the CASS foundation in Melbourne, Australia. The innovative process has been patented in the United States, China and Australia.