Blood or not blood-That is the question. A non-destructive method for the detection of blood-contaminated fingermarks.

Working in crime scenes presents a challenge to the forensic scientist, as some surfaces, such as floors and walls, cannot be transferred to the lab for further development and must, therefore, be processed at the crime scene itself. Two main types of latent fingermarks may be encountered in crime scenes: amino acids based and blood contaminated. One of the most common reagents, which are able to develop both types of fingermarks on porous surfaces, is ninhydrin.