Paper Strips Detect Toxin in Water

Wednesday, January 20 2010

Engineers at the University of Michigan led the development of a new biosensor - a strip of paper infused with carbon nanotubes - that can quickly and inexpensively detect a toxin produced by algae in drinking water.

The paper strips perform 28 times faster than the method most commonly used today to detect microcystin-LR, a chemical compound produced by cyanobacteria, or blue-green algae. Cyanobacteria is commonly found on nutrient-rich waters.

Microcystin-LR (MC-LR) is suspected to cause liver damage and possibly liver cancer, and is among the leading causes of biological water pollution.

Water treatment plants can't always remove MC-LR completely, nor can they test for it often enough, said Nicholas Kotov, a professor in the departments of Chemical Engineering, Biomedical Engineering, and Materials Science and Engineering. The biosensor he and his colleagues developed provides a quick, cheap, portable and sensitive test that could allow water treatment plants and individuals to verify the safety of water on a more regular basis.

The technology could easily be adapted to detect a variety harmful chemicals or toxins.