Sigma-Aldrich Leucomalachite Green

Leucomalachite green has been used as a reagent in presumptive tests which are used to detect invisible blood stains.[1][2]

Leucomalachite green (LMG) is a chief metabolite of malachite green, a triphenylmethane dye that has been used generally as an antifungal drug in the fish industry. DNA adducts formed in livers of rats fed with leucomalachite green have been observed with little mutagenic or carcinogenic effect.[3] LMG is one of the most commonly used reagents for presumptive blood test. It gives a characteristic green color in the presence of blood. LMG destroys DNA in the blood, therefore, the chances of DNA recovery and amplification is reduced or eliminated.[4]