In order to arrest a culprit, police look for fingerprints at the scene of the crime.
Magnetic powder is applied to the surfaces of objects with a magnetic brush to make these latent fingerprints visible. It may now be possible to use latent fingerprints to detect the use of drugs as well.
As reported in the journal Angewandte Chemie, forensic scientists would not even have to change the magnetic brush technique they have used since the 1960s: British scientists at the University of East Anglia in Norwich and King’s College in London have developed a process based on magnetic particles and antibodies that causes fingerprints to fluoresce if they were made by a drug user.
Components of drug metabolites can be detected in sweat. “This also works for the tiny amounts of sweat left behind in the characteristic pattern of grooves and ridges of fingerprints left on the objects that were touched,” explains David A. Russell. To do this, Russell and his team used specially coated magnetic particles with antibodies attached. The antibodies bind specifically to drug components or metabolites. Fingerprints of volunteer test subjects from drug clinics were dusted with this magnetic powder. The prints were then treated with a solution containing an antibody bound to a fluorescing dye. This second antibody binds to the first. If the fingerprint was made by a drug user, it turned yellowish brown. Under visible light, these fingerprints glowed green or red, depending on the fluorescent dye used.
By using the corresponding specific antibodies, the scientists were able to detect THC (the main active component of marijuana), benzoylecgonine (the primary metabolite of cocaine), and methadone and the primary metabolite of methadone in the fingerprints of test subjects. Variation of the antibodies makes it possible to develop detection procedures for other substances of interest.
The characteristic pattern of the fingerprint is maintained. The fingerprints are highly resolved and can be lifted for comparison with known fingerprints, just as in the standard procedure. At higher magnification it is even possible to see the tiny sweat pores along the ridges of the fingertip, which can also be used for unambiguous identification.
“The advantage of this method is that potentially only simple, portable equipment is needed, which can be brought along for a crime scene investigation with no problem,” says Russell. “The magnetic particles make it possible to remove excess reagent with the usual magnetic brush, no complex washing procedures would be needed.”
Author: David A. Russell, University of East Anglia, Norwich (UK), http://www1.uea.ac.uk/cap/people/faculty/dar/
Title: Imaging of Latent Fingerprints through the Detection of Drugs and Metabolites
Angewandte Chemie International Edition 2008, 47, No. 52, 10167–10170, doi: 10.1002/anie.200804348
Researchers invent tiny, light-powered wires to modulate brain's electrical signals
21.02.2018 | University of Chicago
The “Holy Grail” of peptide chemistry: Making peptide active agents available orally
21.02.2018 | Technische Universität München
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
21.02.2018 | Life Sciences
21.02.2018 | Life Sciences
21.02.2018 | Materials Sciences