Professor Bonds With Heavy Metal

Published: Jun 26, 2008
Scientific discovery is sometimes three parts preparation and one part serendipity.

That’s what Joe Laurino, professor of chemistry, found when he discovered a polymer that could be used to remove toxic materials from drinking water, save lives of people exposed to chemical contaminants, and make paint stay on bridges and other metal structures longer, all because it rapidly binds to heavy metal.

Laurino was working on the synthesis of a polymer-based cell membrane when he stumbled upon a compound that bound quickly with metals like lead, nickel, cadmium, silver and aluminum. Since it did not dissolve easily, it made it difficult to determine the complicated structure of the compound.

“Admittedly, at first I was really annoyed, but then I realized its potential,” Laurino said.

Many applications soon came to mind, so Laurino applied for a patent.

One use for the polymer — poly(2-octadecyl butanedioic acid) — could be to filter toxic metals out of water. Lead and other heavy metal ions are usually difficult to get out of water, but after stirring for only 15 minutes, the potentially harmful metal binds to the white powder. The polymer and its bound metal can then be easily filtered, producing clean water. Alternatively, the water could be purified by filtering it through a column containing the compound.

“Surprisingly, the polymer is very efficient in that it binds about 300 times its weight in heavy metals,” Laurino went on to explain. “All of the existing chemical literature says this polymer shouldn’t work that way.”

His group is working with researchers at Marshall University on a project that will test the efficacy of the polymer in animals and humans. Many metals become toxic when ingested in food or water. If turned into a pharmaceutical, the compound could be used to bond with the metal in these patients and then pass through their digestive system safely.

Laurino also believes the polymer will bind with iron, so if it were added to paint, it might help reduce rust and corrosion. A bridge painter based in New England is testing the polymer to see if it will chemically bind the paint to the metal.

The first round of tests, with lead, led to a publication in the Journal of Macromolecular Science. Currently, Laurino and his team of students are further characterizing the polymer’s effectiveness with cadmium, nickel, aluminum, and silver.

“It’s really exciting to work on something so groundbreaking,” said Zubair Ansari, who received the departmental fellowship to work on the project this summer. “It’s like you’re on the front lines of biomolecular research.”