DAPI is a popular blue DNA dye that is used as a nuclear counterstain in fluorescence microscopy, chromosome staining and flow cytometry. The dye binds to the minor groove of dsDNA with approximately 20-fold fluorescence enhancement, with higher affinity for A-T rich regions. DAPI dilactate is essentially the same as DAPI dihydrochloride, but with a different counterion. The dilactate salt form of the dye is more water soluble than the dihydrochloride salt, and therefore DAPI dilactate is a better choice for preparing stock solutions in water.      Classic blue nuclear counterstain for fixed cells  Can be used at higher concentrations to stain live cells  &lamba;Ex/&lamba;Em(DNA) = 358/461 nm  Yellow solid soluble in water  Store at 4°C and protect from light, especially in solution  C22H27N5O6  MW: 457.49