For ease of use and safer handling, we offer both Hoechst 33258 and Hoechst 33342 dissolved in H2O at 10 mg/mL. Hoechst dyes are cell membrane-permeant, minor groove binding blue fluorescent DNA stains. Hoechst 33258 and Hoechst 33342 are spectrally similar. Hoechst 33528 is slightly more water soluble than Hoechst 33342, but both dyes are widely used in cell cycle and apoptosis studies and also as nuclear counterstains. They are typically used to stain live or fixed cells in buffer or medium at 1 ug/mL, with no wash step required.    &lamba;Ex/&lamba;Em (with DNA) = 352/461 nm  Light yellow solution  Store at 4°C and protect from light  C25H27Cl3N6O  MW: 533.88