Scottish researchers say they're having success getting fingerprints from fabric, a feat that traditionally has been difficult for forensic sleuths.
The researcher at the Scottish Police Services Authority (SPSA) and the University of Abertay, Dundee, are experimenting with gold and zinc in a technique called vacuum metal deposition, which is used to find prints on smooth surfaces such as glass and plastic.
Fabrics are placed in a vacuum chamber and coated with evaporated gold as well as zinc, which binds to the gold where there are no fingerprint marks. The resulting impressions indicate where a finger or hand has touched the fabric.
The researchers say they have shown the technique can be used to show a clear fingerprint on fabrics like nylon, silk, and polyester. Fabrics with a high thread count are best for getting prints, the SPSA's Paul Deacon said in a release.
Donor skin dryness affects how clear fingerprints will be. Though full fingerprints are difficult to get from the fabrics, the researchers have been able to produce clear hand impressions.
"An impression of a palm print on the back of someone's shirt might indicate they were pushed off a balcony, rather than jumping," Deacon said. "Fingerprints left on fabric and other surfaces can leave DNA traces, so it can also help forensic scientists to visualize the best area to target on an item of clothing to recover DNA evidence."