Scientists have developed a highly sensitive fingerprint test that can take less than a minute–about 30 seconds–to confirm whether someone has used cocaine.
The breakthrough from the University of Surrey, is a result of the first large scale study of cocaine users and could pave the way for the detection of a range of other Class A substances such as heroin, ecstasy among others.
The non-invasive technology could greatly improve routine drug testing by law enforcement agencies such as the police, prisons, courts among others. It will likely be more portable and more hygienic than testing blood, urine or saliva is currently done in drug abuse detection.
Cocaine is an addictive stimulant made from the coca plant native to South America. It produces a short-term euphoric feeling of energy and talkativeness. Physical effects include a potentially dangerous increase in heart rate and blood pressure.
The study published today (September 22) involved taking fingerprints from a group of patients seeking treatment at drug rehabilitation centres, as well as a larger group not known to be drug users. All of those taking part washed their hands before the test in a variety of ways, and then samples were collected on a prepared chromatography paper. The paper chromatography is a method for separating dissolved substances such as colours and dyes from one another.
The fingerprint is developed using chemicals, so that the ridges of the fingerprint (and therefore the identity of the donor) can be established prior to analysis. Cocaine users excrete traces of two chemicals benzoylecgonine and methylecgonine. Both are excreted by the body’s sweat glands when it metabolizes or break down the cocaine. These chemical are present in fingerprint residue and these traces can still be detected even after hand washing.
The research published in Clinical Chemistry, was carried out with partners from the Netherlands Forensic Institute and Intelligent Fingerprinting. The team, led by Dr Catia Costa and Dr Melanie Bailey from the University of Surrey, developed a new technique to analyse the levels of cocaine detected in the fingerprints. They used chromatography paper to take the sample as part of a technique known as paper spray mass spectrometry.
Dr Costa said: “Paper spray mass spectrometry is gaining increasing popularity in forensic circles because it is incredibly sensitive and is very easy to set up a testing system – the units will save laboratories time.
“This is the first time it has ever been used to detect the presence of drugs in fingerprints, and our results show the technique was 99% effective in detecting cocaine use among the patients.”
Dr Bailey said: “This is a real breakthrough in our work to bring a real time, non-invasive drug-testing method to the market that will provide a definitive result in a matter of minutes – we are already working on a 30 second method.”
“And, as with previous methods we have developed, it is non-invasive, hygienic and can’t be faked – by the nature of the test, the identity of the subject, and their drug use, is all captured within the sample itself.”
“This exciting research clearly demonstrates the important role that fingerprints can play in simplifying drug screening, and complements our own parallel developments in portable, point-of-use diagnostic tests. These activities confirm the value of a fingerprint as a diagnostic matrix,” added Dr Jerry Walker, Intelligent Fingerprinting’s CEO.
“We have supported the University of Surrey research programmes for the last four years, and Dr Bailey and her team have shown time and again that they are the world’s leading group in fingerprint diagnostics research using mass spectrometry. We congratulate them in continuing to expand knowledge in the revolutionary field of fingerprint-based diagnostics.”
At a glance:
Title of the study: Rapid, Secure Drug Testing Using Fingerprint Development and Paper Spray Mass Spectrometry.
Authors: Catia Costa, Roger Webb, Vladimir Palitsin, Mahado Ismail, Marcel de Puit, Samuel Atkinson, and Melanie J. Bailey.
Published: Clinical Chemistry on 22nd September 2017.