Aqueous Leucocrystal Violet can be used to enhance and develop latent prints stained with blood on porous and nonporous surfaces, it can also be used to stain blood marks of shoeprints, swipes and other contact to track where a suspect or victim walked, was dragged or somehow came in contact with the surface.
It will not stain the normal constituents found in latent print residue, so it should only be used in the case of blood contaminated latent prints to be successful. While this solution is an indicator for blood, it may react with other substances not specific to blood. Prior to using Aqueous Leucocrystal Violet, it is recommended to do a presumptive test for blood and to collect a sample of the suspected blood, if visible, for DNA or other blood-type testing. In the kit, there are three bottles, mix them in a precise order and then apply them to the desired surface. The best method of applying Aqueous Leucocrystal Violet is by submersion or washing the solution over the surface, it is NOT recommended to spray this solution except in the case of carpeting to observe shoeprints or other marks in blood. If you are spraying carpet, the development will begin to occur within 30-60 seconds, then blot with paper towels or tissues to remove the excess reagent, begin by spraying lightly with a fine mist to avoid overdevelopment. Aqueous Leucocrystal Violet can be applied by washing it over a horizontal surface, such as a floor or table top. After about 30-60 seconds, blot the excess reagent with tissues. The shelf-life of the unmixed product is one year, once you mix the three chemicals together, the shelf-life is 3 months, if stored in a cool environment. If you are storing it in a hot vehicle, the shelf-life will be considerably less. Since any crime scene is suspected of having blood around it when this product is used, the greater hazard of the blood dictates its disposal and cleanup, cleanup any surfaces and blotting tissues in accordance with the regulations for cleaning the biohazard of blood.