New nanowire combats E. coli pathogens

Meat processing surfaces can be made almost fully resistant to E-coli thanks to new nanowire technology, researchers claim.Scientists at the US University of Arkansas claim to have found a simple but hygienic nanowire coating for titanium surfaces, which almost completely eliminates the food-borne pathogen. "This technology will save meat processors a huge amount of time and money as metal surfaces can now be cleaned in five or ten minutes," said Ryan Tian, an assistant professor of chemistry and biochemistry at the university, told .The resulting nanowire is extremely safe to use in food processing plants, Tian claimed, as when rinsed in water and exposed to ultraviolet light, it kills more than 99 per cent of the E-coli bacteria.It is even resistant to biofilms, colonies of pathogens that form a tough surface skin and resist conventional commercial washing and sanitising methods, he added.The new metal surfaces are also environmentally-friendly, as the heavy chemicals traditionally used to clean dried blood and animal remains are no longer necessary."This process is also extremely sustainable, requiring only that the device be rinsed in reusable water after the heating process," he said.The researchers tested the nanowire coating by examining its effectiveness in fighting the strain of E.coli that is most dangerous to human health, 0157:H7, under UV light.A total of 0.5 ml of an inoculum containing the E. coli strain was dropped on a rectangular glass slide, a titanium plate and a nanowire coated titanium plate, which were then put under regular indoor lighting of a temperature of 20 ° celcius (°C).After five minutes, microbial tests were used to determine the number of E. coli cells on each sample. The results suggested that the titanium plate reduced the number of harmful cells by 37 per cent, and the glass plate by 90 per cent. However, the nanowire coated titanium reduced E-coli cells by a massive 99.99 per cent. The nanowire coated titanium can even be made 100 per cent sterile, Tian said, when immersed in 70 per cent ethanol. This means that it can even for medical procedures such as hip replacements and dental reconstructions.The researchers are currently investigating into whether the technology is equally effective in combating other food-borne illnesses, especially listeria.Nanowire sensing techniques look at the rapid detection of relevant biomolecules using a nanowire with a diameter comparable to the size of an individual biomolecule. The technique offers a direct, real-time detection of captured biomolecules without the usage of a fluorescent, magnetic or otherwise labelled molecule or particle.Nanotechnology as a subject is one of the most hotly-debated topics in the food industry at the moment, with some experts predicting it to be one of the biggest markets of the future.In a report published last month, the consultancy Helmut Kaiser said that the nanotechnology food packaging industry could be worth as much as €22bn ($30bn), based on current market value estimates, while some estimates said the market could be worth €740bn ($1tn) by 2013.Others, however, argue that more research and risk assessment is needed before the technology becomes commonplace.The European Commission recently issues a report stating that more analysis on nanotechnology is needed, as its affect on human health is still largely unknown."Engineered particles of nanometre size can have unique properties and very different effects on health and the environment compared to the same material at larger sizes," said Patrick Von Hove, who edited the publication.Report: Multifunctional nanowire bioscaffolds on titaniumAuthors: W. Dong, T. Zhang, J. Epstein, L. Cooney, H. Wang, Y. Li, Y-B Jiang, A. Cogbill, V. Varadan, Z. Ryan Ting.

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