Laser-Textured Metal Surfaces Kill Bacteria Faster:
Copper surfaces kill microbes that come into contact with them in a matter of hours. A new technique makes the familiar metal even deadlier—by zapping it with lasers.
Bacteria “are becoming more aggressive and resistant to therapeutics; it's the same thing for viruses,” says Rahim Rahimi, a materials engineer at Purdue University and senior author of a paper on the new process, published in April in Advanced Materials Interfaces.
[...] Copper's germ-destroying power, [microbiologist Michael Schmidt] explains, comes from its ability to conduct electricity. When a microbe touches a metal surface, the substance carries electrons away from the microbe's cellular membrane. This reaction sets off a chemical process that ultimately forces open the organism's pores and destroys it.
[...] To enhance the process, Rahimi's team hit a copper sample with laser light for a few milliseconds, thereby creating nanoscale pores in the flat metal and increasing its surface area.
[...] The researchers tested this newly rugged terrain by placing several bacterial strains, including Escherichia coli and a drug-resistant Staphylococcusaureus strain, on both flat and laser-treated pieces of copper. As soon as the cells hit the textured metal, their membranes began to suffer damage; that surface completely eradicated the bacteria, in some cases much more quickly than the untreated one. The surface killed some microbes immediately on contact and took from 40 minutes to two hours to wipe out a full colony, depending on the species and concentration.
Journal Reference:
Vidhya Selvamani, Amin Zareei, Ahmed Elkashif, et al. Hierarchical Micro/Mesoporous Copper Structure with Enhanced Antimicrobial Property via Laser Surface Texturing [$], Advanced Materials Interfaces (DOI: 10.1002/admi.201901890)
(Score: 5, Interesting) by c0lo on Sunday July 19 2020, @11:43PM (1 child)
Nano-spikes are killing E coli/S.aureus at least since 2010. And the electrochemical potential of a metal is not necessary for the kill.
2010 - on silver and on copper [mdpi.com]
2015 - on plastic!! [nih.gov] - electrochemical potential plays no role in this one, the nanotexture does. Even nice, the plastic is nanotextured in molds.
2017 - stainless steel [gatech.edu]
2019 - using Ti-Al alloy [manchester.ac.uk]
2019 - on Ti [frontiersin.org]
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by c0lo on Monday July 20 2020, @10:09AM
There may be something original in this one, tho'.
All the others (that I browsed) ended with a hydrophobic surface - either by texturing alone or by special treatment happening during texturing. However, from TFA(bstract) of this one however:
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford