Angewandte Chemie International Edition 2007, 46, 4100–4103
Fingerprint instead of Blood Sample
Antibody tests on fingerprints to detect drugs and diseases
Contact: David A. Russell, University of East Anglia, Norwich (UK)
Registered journalists may download the original article here:
"Intelligent" Fingerprinting: Simultaneous Identification of Drug Metabolites and Individuals with Antibody-Functionalized Nanoparticles
To this day, fingerprints are just the thing when a perpetrator needs to
be arrested or a person needs to be identified. British scientists
working with David A. Russell also want to make it possible to use
fingerprints to reveal drug and doping transgressions and to diagnose
diseases. As the team from the University of East Anglia in Norwich and
King’s College in London report in the journal
Angewandte Chemie, they have now been able to use specific
antibodies to differentiate between the fingerprints of smokers and
A fingerprint is of no use to an investigator unless it can be matched
to one in a database or can be directly compared with that of a suspect.
Russell and his team expect that we will soon be able to gain
information about the lifestyle of the person who made the fingerprints,
which could shrink the pool of suspects. In this way, it should be
possible to use fingerprints to detect drugs, medications, or food that
have been consumed, and also to diagnose some diseases.
Researchers want to coax all of these secrets out of the tiny traces of
perspiration that a fingerprint leaves on a surface. The research team
demonstrated the ease with which this should be possible by
differentiating between fingerprints made by smokers and nonsmokers. To
avoid false results from chance contact with tobacco products, they
designed their system to detect cotinine, a metabolite formed by the
body after consumption of nicotine. The researchers wet the fingerprints
with a solution containing gold nanoparticles to which cotinine-specific
antibodies were attached. These bind to the cotinine. Subsequently, a
second antibody, which was tagged with a fluorescent dye and binds
specifically to cotinine antibodies, was applied to the fingerprint.
Because there are many cotinine antibodies attached to each nanosphere,
there is a significant amplification effect.
Indeed, the ridge patterns of smokers’ fingerprints fluoresce, while
those of nonsmokers do not. The fingerprints are very highly resolved
and can be lifted for comparison with known prints, just as in
conventional procedures. When magnified, even the tiny sweat pores along
the ridges of the fingertip become visible, which can also be used to
make an unambiguous assignment.
In addition to forensic applications, this method would be ideal for
detecting doping. Sample manipulations by the test subjects would hardly
be possible since each sample is uniquely assignable to a specific
athlete by virtue of the ridge pattern. Medical diagnostics could also
benefit in the form of simple and quick mass screening with no danger of
sample mix-ups. Another application could be drug screening without
taking blood samples—from suspicious drivers, for example.