Breaking Good: Detecting meth

Skip to Navigation

Ezine

  • Published: Jul 1, 2014
  • Author: David Bradley
  • Channels: Infrared Spectroscopy
thumbnail image: Breaking Good: Detecting meth

Neurotoxic psychostimulant

In the journal Angewandte Chemie, Italian researchers have now introduced a new method of detection that allows the entire class of methamphetamine drugs to be detected in water.

Illicit methamphetamine abuse is now widespread as is the abuse of related, so-called designer drugs. Research from Italy published in the journal Angewandte Chemie shows that it is possible to detect these chemicals readily in water.

Methamphetamine is a contraction of N-methyl-alpha-methylphenethylamine, a potent psychostimulant and neurotoxin that has been used rarely in the treatment of attention deficit hyperactivity disorder (ADHD) and obesity. It is more familiar as a drug of abuse and its unlicensed sale on the black market represents a serious health risk to users as well as a multimillion dollar international criminal trade. Its recreational use is associated with an energetic chemical "high" and increased libido and sexual stamina. It has potential for addiction and at high dose can cause psychosis and cerebral haemorrhage. Numerous psychoactive derivatives exist and black market chemists are continually developing novel analogues sold as "legal highs" to stay ahead of legislation. These novel compounds are as troublesome for society as the parent compound in terms of criminality.

Fight or flight

As such, a simple analytical technique that can test for methamphetamines in water, would be useful for law enforcement. A probe equipped with synthetic receptor molecules that responds to a grouping of atoms present in all methamphetamines has now been developed. Because the peripheral functional or non-functional groups are irrelevant to detection, this test can find all variations on the theme and so is not limited to a single drug. The new test should also be much quicker to implement than any conventional analysis for the individual drugs as well as precluding the need for sophisticated sample preparation.

A large variety of analytical methods for the detection of methamphetamines have been developed, most of which are slow to yield results or require complicated operations such as labour-intensive sample preparation, among them solid-phase extraction followed by gas chromatography/mass spectrometry (GC-MS), liquid chromatography/mass spectrometry (LC/MS), ion trap mobility spectrometry and GC-Fourier transform infrared spectroscopy and and various immunoassay methods. The designer variants of methamphetamines all have different levels of activity but are essentially the same at the basic structural level acting as agonists for the trace amine-associated receptor 1 (TAAR1), a G protein-coupled receptor (GPCR) that regulates brain catecholamine systems. The body's natural catechols (basically benzene rings with two hydroxyl groups and various side chains) include epinephrine (adrenaline), norepinephrine (noradrenaline) and dopamine. Interfering with, or activating, the brain's receptors for these compounds will, of course, trigger reactions, such as the fight-or-flight response, sexual arousal and other physiological effects commonly associated with methamphetamine abuse. Those designer variants exist simply to avoid detection by the standard methamphetamine tests.

Generic meth detection

The scientists who developed the wholly generic methamphetamine test are from the Universities of Parma, Brescia, and Catania and their work successfully meets the challenge facing law enforcement working in the face of clever criminal chemists. The new technique is based on molecular recognition and a nanomechanical detector. In work led by Paolo Bergese and Enrico Dalcanale involved grafting a cavitand designed to recognise the methylamino group on the basic methamphetamine skeleton on to a silicon cantilever. Such cantilevers are usually used as probes in atomic force microscopy (AFM). An array of such grafted cantilevers is used to probe the surface of an aqueous sample. If a cavitand comes into contact with a methamphetamine molecule, the molecule is bound. This molecular recognition is transformed into a mechanical response, which is converted into a deflection of the cantilever.

The cavitands recognise the methylamino group through a synergistic set of weak interactions. The chemical variations inherent in designer drugs do not interfere with the recognition by the synthetic receptor. Other substances typically mixed with the drug, usually glucose or lactose, do not disturb the detection either. The researchers were able to demonstrate the effectiveness of their technique with a variety of methamphetamine-based substances as well as real samples from the street.

"Our next step is twofold," Dalcanale told SpectroscopyNOW, "a fluorescent sensor specific for detecting MDMA in water/urine and using this approach for theragnostics (delivery of cancer drugs)."

Related Links

Angew Chem Int Edn, 2014, 53, online: "Cavitand-Grafted Silicon Microcantilevers as a Universal Probe for Illicit and Designer Drugs in Water"

Article by David Bradley

The views represented in this article are solely those of the author and do not necessarily represent those of John Wiley and Sons, Ltd.

Social Links

Share This Links

Bookmark and Share

Microsites

Suppliers Selection
Societies Selection

Banner Ad

Click here to see
all job opportunities

Most Viewed

Copyright Information

Interested in separation science? Visit our sister site separationsNOW.com

Copyright © 2017 John Wiley & Sons, Inc. All Rights Reserved