A polymer that gives an instantaneous fluorescence and colour change in response to tiny amounts of water could prove useful for in fingerprinting techniques, reports a paper published in Nature Communications this week. The method reported in this work proved sensitive enough to detect individual sweat pores in the human hand leading to detailed colour-based copies of fingerprints.
The idea of using sweat pores as a means of fingerprint detection was proposed early on in the development of the science, but inexpensive, rapid and reliable methods to map pores have proven difficult to achieve. Jong-Man Kim and colleagues now describe a simple polymer based material that can be printed with ink-jet technology and, when a finger is presented, gives an immediate response, sensitive enough even to distinguish functioning pores from those that are inactive.
Typically the ridge patterns on fingertips are used for generating fingerprints, and these require large portions of the fingerprint for reliable analysis. Using sweat pores allows pattern recognition with even small fractions of the latent print, which suggests that this method may provide for more detailed and reliable fingerprinting.