Himedia EZdetect Hoechst Stain Kit for Mycoplasma Detection

The EZdetectTM Hoechst stain kit has been designed for detection of mycoplasma based on rapid uptake of the fluorescent stain Hoechst by cellular DNA. The dye itself exhibits high permeability into cells; a property that facilitates quick uptake by the cells. It selectively binds minor grooves of the DNA and hence allows for efficient staining of the nuclei. The excitation and emission spectra of Hoechst bound to dsDNA are similar to dsDNA bound to DAPI, with excitation maxima around 350-360nm and emission maxima around 450-460nm. Hoechst stain can be excited either with a xenon mercury arc lamp or a UV laser and is detected through a blue filter. Mycoplasma staining with Hoechst appears as a fine particulate or filamentous staining over the cytoplasm at 100X magnification. Nuclei of the cells are also brightly stained by this method and thereby act as endogenous positive control for the staining procedure.