They can sense dangerous chemicals and biological agents

Jul 9, 2009 10:25 GMT  ·  By

Metal-oxide nanoparticles are among the most commonly used in the industry, because they are relatively easy to produce, and can be grown in very small sizes. Now, their production process has been refined even further, as experts from the Ohio State University (OSU) have developed a new process for creating them smaller and purer. The creators describe the process as simple, fast, and demanding very few resources, as compared with others. In addition, they report, it takes place at low temperatures.

OSU Associate Professor of Materials Science and Engineering Patricia Morris, the leader of the research team at the university, explains that the greatest challenge the experts had to face was developing nanoparticles that would react extremely fast when they came in contact with toxic industrial chemicals (TIC), or biological warfare agents. She also underlines the fact that the new research was specifically aimed at improving existing gas detectors, which deal with this sort of dangerous substances. In detecting them, every moment counts, Morris believes, and the reaction speed of particles is essential.

“These are sensors that a soldier could wear on the battlefield, or a first responder could wear to an accident at a chemical plant,” the researcher says. Because of its unusual electrical properties, the team decided to orient its effort towards researching nickel oxide structures, as they held the most promises in a large array of fields, ranging from battery and fuel-cell production to solar-cell improvements and color-shifting coatings or paints. “The human nose coordinates signals from hundreds of thousands of sensory neurons to identify chemicals. Here, we're using a combination of electrical responses to identify the signature of a toxic chemical,” OSU doctoral student Elvin Beach shares.

The two experts say that the way in which the sensor is constructed is its most important aspect. If the nanoparticles on it were as small as possible, then the overall surface of the device would be larger, which means that it would allow it to capture more of the substances it analyzed. Additionally, if the particles themselves were pure, then they could detect the slightest concentrations of dangerous chemicals around them, on account of the fact that their detection “sense” was not hindered by residues.