NIST method detects explosives

A chemist at the National Institute of Standards and Technology (NIST) has developed a simple method for detecting and measuring small quantities of explosives that is claimed to be more sensitive than conventional techniques.

NIST researcher Tom Bruno enhanced a technique called 'headspace analysis', which is used to detect and analyse trace levels of chemical compounds from solids or liquids that are released into the atmosphere.

Bruno’s enhancements improved the efficiency of sample collection, for the first time making the technique suitable for detecting low concentrations of polar, low-volatility compounds such as explosives.

Preliminary results indicate the method is sensitive enough to measure amounts of target materials that constitute as little as 0.0000002 per cent of a sample.

The sample collection device consists of several coils of fine tubing, just 0.32mm in inner diameter, whose inner coating has been modified to efficiently attract and retain chemicals across its large surface area.

The device can be used with a sample-heating oven as part of a laboratory analysis system or taken into the field for sample collection.