Malachite green also is used as a direct dye for silk, wool, jute, and leather and to dye cotton that has been mordanted with tannin. Prepared from benzaldehyde and dimethylaniline, the dye occurs as lustrous green crystals soluble in water and in alcohol. However, the dye has generated much concern regarding its use, due to its reported toxic effects. The toxicity of this dye increases with exposure time, temperature and concentration. It has been reported to cause carcinogenesis, mutagenesis, chromosomal fractures, teratogenecity and respiratory toxicity.

Malachite Green Solution provides a simple and convenient method for detection of lipid and protein phosphatases. Simply mix the solution with a room temperature phosphatase reaction, incubate 15-30 min, then read 

Malachite green (MG) is water soluble cationic dye that appears as green crystalline powder and belongs to triphenylmethane category

use fresh millipored water. 75ml of 0.045%(w/v) malachite green solution (BDH stock solution is 0.5%, 9ml in 100ml -> 0.045%). Stir for at least 30 minutes (don't miss this out, it is important), filter through 0.22µm syringe filter. You get a green solution which on filtering is amber.

MALACHITE GREEN SOLUTION