Wiping away infection risks

A researcher from Cornell University has developed a moist wipe which can detect bacteria, viruses and other dangerous substances in hospitals, aeroplanes and in food processing.

‘It’s very inexpensive, it wouldn’t require that someone be highly trained to use it, and it could be activated for whatever you want to find,’ said Margaret Frey, the Lois and Mel Tukman Assistant Professor of Fibre Science and Apparel Design at Cornell.

‘So if you’re working in a meat-packing plant, for instance, you could swipe it across some hamburger and quickly and easily detect E. coli bacteria.’

Once fully developed, the biodegradable absorbent wipe would contain nanofibres containing antibodies to numerous biohazards and chemicals and would signal by changing colour or through another effect when the antibodies attached to their targets. Users would simply wipe the napkin across a surface. If a biohazard were detected, the surface could be disinfected and retested with another napkin to be sure it was no longer contaminated.

Frey developed nanofibres with platforms made of biotin, a part of the B vitamin complex, and the protein streptavidin, which can hold the antibodies. Composed of a polymer compound made from corn, the nanofibres could be incorporated into conventional paper products to keep costs low. Nanofibres, with a diameter near 100 nanometres, provide extremely large surface areas for sensing and increased absorbency compared with conventional fibres.

‘The fabric basically acts as a sponge that you can use to dip in a liquid or wipe across a surface,’ Frey said. ‘As you do that, antibodies in the fabric are going to selectively latch onto whatever pathogen that they match. Using this method we should, in theory, be able to quickly activate the fabric to detect whatever is the hazard of the week, whether it is bird flu, mad cow disease or anthrax.’

Frey and her colleagues are still working on ways, such as a colour change, for the fabric to signal that it has identified the contaminant.

‘We’re probably still a few years away from having this ready for the real world,’ Frey said, ‘but I really believe there is a place for this type of product that can be used by people with limited training to provide a fast indication of whether a biohazard is present.’