Methods Used to Lift Fingerprints from Surfaces:

Powder And Tape: This is probably the most well-known method of detecting latent prints. A variety of powders are used in dusting for prints, many containing either aluminum or carbon. This finely crushed powder is gently applied to a surface, and the small particles of powder stick to the residue that the print leaves, making it visible to the human eye. These prints are then lifted using tape. For dusting to work, the surface that is being dusted must be completely dry and relatively free of other contamination.

Magna Brush: This is a magnetic wand that attracts iron. It is dipped in iron dust, and the particles cling to it. This is then used the same as dusting using carbon and aluminum powders. The Magna Brush is also less messy, as any excess iron particles can be easily collected with the Magna Brush. There are many colors available for this, and some of these powders reflect alternative light sources such as UV and lasers.

The Cyanoacrylate Fuming Method: Also known as the superglue fuming method, the cyanoacrylate fuming method has proved to be another very useful way of detecting latent prints. This method was first used by the Criminal Identification Division of the Japanese National Police Agency in 1978. Shortly after this it was adopted in the US, and now it is a commonly used method of detecting prints. They basically use super glues to do this process. This reacts with the traces of amino acids, fatty acids, and proteins in fingerprints as well as the moisture in the air, making them visible.

Ninhydrin:Another common method of fingerprint detection is the use of ninhydrin. This is sprayed, swabbed or dripped onto the surface. Ninhydrin reacts with the amino acids in the prints, forming a purple or pink compound.

Iodine Fuming: Iodine crystals are placed in a glass tube known as a fumer. The examiner then blows into the fumer, causing the transformation from solid to gas. The iodine vapours are emitted from the other end, and if the tube is aimed at a latent print, it will become visible for a short time.

Silver Nitrate: Silver Nitrate is a less toxic way of detecting prints on paper. Silver chloride turns black in light, and one of the components of sweat is sodium chloride. The silver nitrate is placed with distilled water and applied to the paper. The paper is exposed to light, and any prints will turn black.