Hidden fingerprints revealed

March 15, 2007

Hidden fingerprints can be now be revealed quickly and reliably thanks to two developments in nanotechnology. The news is reported in the latest edition of the Royal Society of Chemistry journal Chemical Communications.

The current method for revealing prints involves coating surfaces with a watery suspension of gold nanoparticles and citrate ions. Under acid conditions, the gold particles stick to the positively charged particles in the print.

The print is then developed using a solution of silver ions, which chemically react to leave an outline of silver along the ridges of the print.

However, the gold solution used in this method is unstable and results are difficult to repeat – so Dr Daniel Mandler, Dr Joseph Almog and their team at the Hebrew University of Jerusalem, Israel, have developed a more stable solution be adding hydrocarbon chains to the gold nanoparticles and suspending them in petroleum ether.

The prints produced using the new solution are very high quality and are developed after just three minutes immersion time.

The team have also extended their technique for use on non-porous surfaces, using a petrol ether suspension of cadmium selenide/zinc sulphide. In this case, the chemical reaction makes the prints fluoresce, so no additional developing stage is required.

Antonio Cantu, an expert in forensic science for the United States Secret Service in Washington, said: “The techniques are revolutionary and are apt to greatly improve the recovery of latent prints on evidence.”

Dr Claude Roux, director of the Centre for Forensic Science at the University of Technology, Sydney, Australia, said: “This use of nanotechnology in the fingerprint community can bring novel and practical solutions to develop and enhance latent fingerprints that would otherwise remain undetected.”

Source: RCS

Explore further: Could cryptocurrency help the 'bottom billion'?

Related Stories

Could cryptocurrency help the 'bottom billion'?

October 17, 2016

Many of the world's poorest poor don't have access to a bank account and yet depend on being able to transfer money across borders. Could digital currency help, ask researchers at the Cambridge Centre for Alternative Finance.

Hot off the press: Nanoscale Gutenberg-style printing

April 15, 2011

(PhysOrg.com) -- When Gutenberg developed the principles of modern book printing, books became available to the masses. Hoping to bring technology capable of mass production to the nanometer scale, Udo Bach and this team ...

3-D printing with metals achieved

June 10, 2015

A team of researchers from the University of Twente has found a way to 3D print structures of copper and gold, by stacking microscopically small metal droplets. These droplets are made by melting a thin metal film using ...

Innovative solutions for urban mining

May 30, 2013

Urban mining is a performed by extracting metal resources from electronic products. Gold from PCBs and Lithium from seawater - read more about Prof. Jai-Koo Park of Hanyang University on his research into urban mining.

Recommended for you

ANU invention to inspire new night-vision specs

December 7, 2016

Scientists at The Australian National University (ANU) have designed a nano crystal around 500 times smaller than a human hair that turns darkness into visible light and can be used to create light-weight night-vision glasses.

New method for studying individual defects in transistors

December 6, 2016

Scientists from the University of Twente's MESA+ Research Institute have developed a method for studying individual defects in transistors. All computer chips, which are each made up of huge numbers of transistors, contain ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.