Successful convictions in the fight against rising gun crime could be given a boost thanks to new DNA tagging technology developed by scientists at the University of Surrey.

The breakthrough uses nanotechnology to coat gun cartridges which captures the user’s DNA. These ‘nanotags’ are also easily transferred to the user’s hands and clothing and are difficult to wash off, making it harder for gun criminals to cover their tracks.

The technology was developed by a conglomerate of UK universities (Brighton, Cranfield, York and Brunel), and led by the University of Surrey. The results are a significant step forward in the fight against gun crime as current forensic testing is limited and often unreliable as DNA evidence is easily destroyed and gun residue cannot always be traced on the user. The work was funded by the Engineering and Physical Sciences Research Council (EPSRC).

  (Fig 1 - Nanotechnology particles)

The tags are created by coating naturally occurring pollen grains with nanotechnology particles (fig 1). They are then coated onto the gun cartridge creating an abrasive surface much better suited to retaining skin cells than the cartridge’s smooth finish. Currently the majority of DNA is destroyed by the heat created when a gun is fired, but the chemical coating can withstand these temperatures which means the evidence survives, leaving a trail of clues for police.

Additionally, the composition of the coating can be chemically manufactured to make each batch of cartridges unique, allowing police to establish a clear link between the user and a fired cartridge. 

"This technology has the potential to become a key tool for police in the fight against gun crime," commented research leader Professor Paul Sermon, from the University of Surrey. "The use of nanotechnology means we have at our disposal a much more reliable way of linking the gun, cartridge and user which has not been available before. The increased chances of being caught could therefore also deter criminals from using guns in the first place."