properties of matter : Each tablet contains 5mg of DAB for quick and easy preparation of substrate solution. When dissolved in 10 ml of deionized water, each 240 mg total weight tablet prepares an optimized substrate solution (pH5.0) that remains stable for 2-3 hours at room temperature. It is enough to effectively detect 50cm2 of membrane or about 20 slides. Simply add 0.1% Hydrogen Peroxide immediately before use.