The possible use of chemical-warfare agents in terrorist attacks has increased the need for reliable and accurate methods to detect these lethal chemicals.

Ana M. Costero, Ramón Martínez-Máñez and co-workers, Universidad de Valencia, have developed a chromo-reactant for the selective detection of Tabun versus other nerve gases, such as Sarin and Soman. Since one of the antidotes is ineffective in treating Soman poisoning, distinguishing between these members of the nerve gas family can literally be a matter of life and death.

The sensing protocol uses an azo dye, in which the pyridine and aniline moieties can selectively detect the different agents by color changes. Addition of diisopropylfluorophosphate (a Sarin mimic) and diethylchlorophosphate (a Soman mimic) causes phosphorylation of pyridine (change from orange to magenta), whereas addition of diethylcyanophosphonate (a Tabun mimic) causes phosphorylation of aniline (change from orange to yellow).

• Chromogenic, Specific Detection of the Nerve-Agent Mimic DCNP (a Tabun Mimic)
  S. Royo, A. M. Costero, M. Parra, Dr. S. Gil, R. Martínez-Máñez, F. Sancenón
  Chem. Eur. J. 2011.
  DOI: 10.1002/chem.201100602