Tri-Tech Forensics Extra-Strength Ninhydrin Spray, 8 oz

Our quick drying Ninhydrin Spray is supplied in an easy-to-use pump misting bottle and is an extremely sensitive method for developing old latent prints on paper documents, letters, newspaper, envelopes, wrapping paper, checks, and even wallpaper at a crime scene.

Ninhydrin reacts to the proteins and amino acids found in fingerprints. When ninhydrin is sprayed on the suspected area, the print will appear purple in color when heated to approximately 220 degrees in an oven or with a hair dryer or infrared lamp.

Because it requires less technique than using Small Particle Reagent or other methods, Ninhydrin is a simple way to develop latent print on the "sticky side" of duct and clear tape. Simply mount the tape, sticky side out, on a sheet of cardboard, then spray the tape with Ninhydrin and let the tape sit at room temperature. Usable patterns will begin to appear within one to two hours and, after approximately 24 hours, clearly identifiable prints will develop.

Normally, heat is used to speed up the development of prints treated with Ninhydrin; however, applying heat to the tape can result in the tape adhesive melting or cause the tape to wrinkle which will either destroy or distort the print.

After photographing the print, it is then sprayed with a Ninhydrin Print Fixative to preserve the Ninhydrin. The developed print is then protected by affixing either lifting tape or the cover of a hinged lifter to the tape.