A simple magnet can go a long way toward eliminating bacteria.
Xuefei Huang and his colleagues at the University of Toledo in Ohio coated nanoparticles of rusty iron with sugary molecules normally found on the membranes of mammalian cells. Different bacteria bind to specific types of such molecules when they attack cells.
The researchers targeted three strains of Escherichia coli with nanoparticles coated with each strain's favorite sugars. The particles quickly stuck to the bugs. The researchers applied a magnet, which immediately began pulling the nanoparticles' bacteria in tow. After 45 minutes, the magnet had dragged out 88 percent of the E. coli, Huang and his colleagues report in the Nov. 7 Journal of the American Chemical Society.
Huang says that the nanoparticles could be designed to quickly detect specific pathogens, including viruses. "If you see a white powder and you suspect it's anthrax, you want to detect it within a few minutes," he notes.
So far, the method detects only microbes that are present in sizable numbers, but Huang says using fluorescent sugar molecules might bring the sensitivity down to single cells. Because the nanoparticles could be cheap to produce, they could also help in decontaminating water supplies, Huang says.
Department of Chemistry
University of Toledo
2801 West Bancroft Street
Toledo, OH 43606