New copper surface eliminates bacteria in just two minutes, scientists
report

Date:
December 13, 2021
Source:
RMIT University
Summary:
A new copper surface that kills bacteria more than 100 times faster
and more effectively than standard copper could help combat the
growing threat of antibiotic-resistant superbugs.



FULL STORY ==========================================================================
A new copper surface that kills bacteria more than 100 times faster
and more effectively than standard copper could help combat the growing
threat of antibiotic-resistant superbugs.


==========================================================================
The new copper product is the result of a collaborative research project
with RMIT University and Australia's national science agency, CSIRO,
with findings just published in Biomaterials.

Copper has long been used to fight different strains of bacteria,
including the commonly found golden staph, because the ions released
from the metal's surface are toxic to bacterial cells.

But this process is slow when standard copper is used, as RMIT
University's Distinguished Professor Ma Qian explained, and significant
efforts are underway by researchers worldwide to speed it up.

"A standard copper surface will kill about 97% of golden staph within
four hours," Qian said.

"Incredibly, when we placed golden staph bacteria on our
specially-designed copper surface, it destroyed more than 99.99% of
the cells in just two minutes." "So not only is it more effective,
it's 120 times faster."


========================================================================== Importantly, said Qian, these results were achieved without the assistance
of any drug.

"Our copper structure has shown itself to be remarkably potent for such
a common material," he said.

The team believes there could be a huge range of applications for the new material once further developed, including antimicrobial doorhandles and
other touch surfaces in schools, hospitals, homes and public transport, as
well as filters in antimicrobial respirators or air ventilation systems,
and in face masks.

The team is now looking to investigate the enhanced copper's effectiveness against SARS-COV-2, the virus that causes COVID-19, including assessing
3D- printed samples.

Other studies suggest copper may be highly effective against the virus,
leading the US Environmental Protection Agency to officially approve
copper surfaces for antiviral uses earlier this year.



========================================================================== Unique structure brings more copper to the fight Study lead author,
Dr Jackson Leigh Smith, said the copper's unique porous structure was
key to its effectiveness as a rapid bacteria killer.

A special copper mould casting process was used to make the alloy,
arranging copper and manganese atoms into specific formations.

The manganese atoms were then removed from the alloy using a cheap and
scalable chemical process called "dealloying," leaving pure copper full
of tiny microscale and nanoscale cavities in its surface.

"Our copper is composed of comb-like microscale cavities and within
each tooth of that comb structure are much smaller nanoscale cavities;
it has a massive active surface area," Smith said.

"The pattern also makes the surface super hydrophilic, or water-loving,
so that water lies on it as a flat film rather than as droplets."
"The hydrophilic effect means bacterial cells struggle to hold their
form as they are stretched by the surface nanostructure, while the
porous pattern allows copper ions to release faster." "These combined
effects not only cause structural degradation of bacterial cells, making
them more vulnerable to the poisonous copper ions, but also facilitates
uptake of copper ions into the bacterial cells," Smith said.

"It's that combination of effects that results in greatly accelerated elimination of bacteria." Dr Daniel Liang of CSIRO said researchers
across the world were looking to develop new medical materials and
devices that could help reduce the rise of antibiotic-resistant super
bugs by reducing the need for antibiotics.

"Drug-resistant infections are on the rise, and with limited new
antibiotics coming onto the market, the development of materials resistant
to bacteria will likely play an important role in helping address the
problem," Liang said.

"This new copper product offers a promising and affordable option to
fighting superbugs, and is just one example of CSIRO's work in helping
to address the growing risk of antibiotic resistance." This study
was initiated through an RMIT-CSIRO PhD program and was subsequently
co-funded by the CASS Foundation Melbourne, Australia. The innovative
process now has patents pending in the USA, China and Australia.

========================================================================== Story Source: Materials provided by RMIT_University. Original written
by Michael Quin. Note: Content may be edited for style and length.


========================================================================== Journal Reference:
1. J.L. Smith, N. Tran, T. Song, D. Liang, M. Qian. Robust bulk
micro-nano
hierarchical copper structures possessing exceptional bactericidal
efficacy. Biomaterials, 2022; 280: 121271 DOI: 10.1016/
j.biomaterials.2021.121271 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/12/211213121829.htm

--- up 1 week, 2 days, 7 hours, 13 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)