ChemCafé

When inhalated, organophosphorus compounds can cause death within minutes. Although they are prohibited by the Chemical Convention Weapons, several states still possess large stockpiles of these chemicals, and terrorist organisations are not particularly known for complying with international conventions – one of these organophosphorus compounds is sarin, (in)famous for having been spread in the Tokyo subway by the sect Aum Shinrikyo in 1995, killing 12 people and injuring a thousand others.

In this context, lots of effort is dedicated to find ways to detect and destroy such compounds before they can cause harm. An appealing solution was recently proposed by a research team led by Julius Rebek, Jr. at the Scripps Institute. In an article recently published in Angewandte, they show how their novel molecules can signal the presence of organophosphorus compounds, but also render them harmless by undergoing a rapid reaction.

The sensing systems is based on an aromatic ring equipped with an oxime group (C=N-OH), which is known to react with organophosphorus compounds. The intermediate product instantaneously reacts further (which is important since at this point, the toxicity survives) to form a harmless decomposition compound and a fluorescent unit, which is used to signal the fact that the reaction has occured, and therefore the presence of toxic chemicals! Really smart approach!

References:
T. J. Dale, J. Rebek, Jr. Angew. Chem., Int. Ed. 2009, 48, 7850 –7852. DOI: 10.1002/anie.200902820

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