
The standard way of finding hidden fingerprints currently used by investsigators involves coating the surface with gold particles and developing with a reagent called silver physical developer which reacts to create a black silver precipitate along the fingermark ridges. This developer is unstable and results can vary. With the new gold nanoparticle technique, the recovery of prints on evidence can be greatly improved.
Now it remains to be seen when this technology starts to be used on TV — and in the real world.
Source: Nanotechnology reveals hidden fingerprints