DFO Spray, also known as 1,8-Diazafluoren-9-one, is a Ninhydrin analogue that responds to amino acids and causes latent prints to fluoresce under a forensic light source. DFO Spray is for use on porous surfaces such as paper, photos, or cardboard. DFO Spray can be used alone or in conjunction with Ninhydrin, although it should always be used before Ninhydrin. Research suggests that DFO Spray may develop latent prints better than Ninhydrin alone.
The DFO is used by spraying the solution onto the item in question. The latent prints will develop over time or development can be accelerated by heating the item at 100° C (212° F) for approximately 10 - 20 minutes.
To view the developed print, use a forensic light source in a dark room. DFO fluoresces well between 450 and 530 nanometers. At this point, the print should be photographed and kept as evidence.
We offer two formulas of DFO Spray in 4 oz bottles. You can choose from a traditional formula (Reorder No. CHE-3125) or a non-flammable HFE-7100 formula (Reorder No. CHE-3137).