Fingerprint test can distinguish between those who have taken or handled cocaine
For drug testing, it is necessary to be able to distinguish those who have handled cocaine from those who have ingested it because the legal ramifications are different for example, consider drug driving the new research demonstrates that this is possible for the first time using high resolution mass spectrometry techniques.
A successful, commercially available fingerprint drug screening system, using lateral flow assay technology and fluorescence labelled antibodies to selectively detect specific drugs or their metabolites in eccrine sweat collected from fingerprints, is already available for point of care use from Intelligent Fingerprinting who also offer a fingerprint based laboratory confirmation service which uses Liquid Chromatography Mass Spectrometry techniques.
The team, from University of Surrey, Forensic Science Ireland, National Physical Laboratory and Intelligent Fingerprinting, took fingerprints from people seeking treatment at drug rehabilitation clinics who had testified to taking cocaine during the previous 24 hours.
Fingerprints were collected from each patient, and the participants were then asked to wash their hands thoroughly with soap and water before giving another set of fingerprints.
This same process was used to collect samples from a pool of drug non users who had touched street cocaine.
The researchers at Surrey used their world leading experimental fingerprint drug testing approach (based on rapid, high resolution mass spectrometry) to cross reference the information from the drug non users who had touched cocaine with that of volunteers who testified ingesting it.
They found that a molecule produced in the body when cocaine is ingested, benzoylecgonine, is essential in distinguishing those who have consumed the class A drug from those who have handled it.
Benzoylecgonine was not present in samples from drug non users, even after touching street cocaine and then washing their hands. ■