An on the spot detector for ecstasy tablets has been made by scientists in Spain. The probe has been designed to detect the active ingredient in ecstasy - MDMA (3,4-methylenedioxymethamphetamine) - even when it is mixed with other common additives, which has been a challenge.

One way to detect ecstasy is a colorimetric test, but the test is not specific for MDMA and is unable to distinguish it from amphetamine and other common phenethylamines. Another method is chromatography, which can distinguish between these compounds but isn’t portable. Now, Tom?s Torroba and his team from the University of Burgos have made a fluorimetric compound that can be used to identify MDMA. ’The fluorogenic probe may be used as an in situ test for fast detection. It only needs a small sample and can be checked with a portable ultraviolet lamp,’ says Torroba.

The probe - a diaryl urea tagged with two fluorescent indicator units - is selective for primary and secondary amines, so it can only reveal that a primary or secondary amine is present. ’It would be difficult to distinguish the difference between amphetamine or MDMA by the naked eye,’ says Torroba. ’A mathematical trick is required.’

So, the team used a fluorimeter to measure several parameters and ran the resulting numbers through an algorithm. This converted the numbers into a two-dimensional plot in which each component was placed in a different region of the plot. So this standard plot can be used to check for MDMA and other amphetamines in real samples.

To test the method’s ability to pick out MDMA when it’s mixed with other compounds, the team used it with a tablet consisting of MDMA mixed with sucrose, chalk and caffeine. They compared the fluorescent signal with that of pure MDMA and found that the signals were identical.

’Many tablets of street ecstasy are not pure MDMA and frequently include amphetamines (and may also contain dextromethorphan, caffeine, MDA, ephedrine etc), which may trigger false drug test results,’ says Jorge Garrido, who studies amphetamines at the Polytechnic Institute of Porto, Portugal. ’Developing new analytical methods to overcome such a critical limitation is of the utmost importance.’

Elinor Richards