Originally published by How It Works Magazine.
A UK company called Intelligent Fingerprinting has developed a new form of non-invasive drug screening: a handheld device that detects the breakdown products of commonly abused drugs in sweat released through the pores of the fingertips.
How It Works
An image of the fingerprint is taken to establish a reference point, and the fingerprint is treated with a solution containing gold nanoparticles that bind to the breakdown products of illicit substances. The particles are stained with a fluorescent dye, and a second image of the print is taken.
This test is much quicker than alternative methods (it takes only about 10 minutes) and provides proof that a positive result belongs to the fingerprint’s owner and is not due to sample contamination. Sweat is released from pores in the fingertips and eventually flows along the fingerprint ridges, carrying traces of drug metabolites whose concentrations gradually decrease. If the staining of the print is greatest at the pores, it provides solid evidence that the metabolites are being released from the sweat glands of the person being tested.
