Daily news

8 November 2003

Nanoparticles clearly finger the culprit

Oil-seeking nanoparticles could give police the clearest fingerprints yet, suggests new research.

Law enforcement officers currently search for prints by dusting a crime scene with fluorescent powder. This sticks to the oily residue left by the fingertip, showing up the whorls and ridges. But sometimes the prints are not clear enough to finger a suspect.

The new dust made of sticky nanoparticles could help. The powders used today work because oily prints have a natural tackiness. But the nanoparticle dust being developed at the University of Sunderland in the UK will actively seek out any oil.

The nanoparticles are tiny glass spheres between 200 and 600 nanometres in diameter. As well as being speckled with a fluorescent dye, they are coated with hydrophobic molecules, which are repelled by water and attracted to oil. So they fix tightly to the fingerprint.


Fred Rowell, who is leading the research, says the nanoparticles should pick out even the faintest of fingerprints because they stick to tiny traces of oil. And the prints should be much sharper, providing fine detail that can be crucial to identifying a print, such as how ridges in the print branch and finish.

While the research is in its early stages, Rowell hopes he piqued the interest of the police by presenting the project at the Nanotechnology in Crime Prevention and Detection conference held in London last week.