Ethidium Homodimer III, also known as EthD-III, is a red fluorescent dead cell stain for bacteria and mammalian cells. It is a cell membrane-impermeant nucleic acid dye that stains only dead cells with damaged cell membranes. Ethidium Homodimer III was developed by Biotium as a superior alternative to Ethidium Homodimer I. The absorption and emission spectra are similar, but EthD-III is 45% brighter.

• Dead cell-specific DNA stain
• Can be used in mammalian, yeast, and bacteria cells
• 45% brighter than Ethidium Homodimer I
• Provided as a red solid

Ethidium Homodimer III is membrane impermeant and useful for selectively staining dead cells with damaged plasma membranes. It also is a component of several combination viability assay kits for detecting both live and dead cells in the same population, such as our Viability/Cytotoxicity Assay Kit for Animal Cells (Cat. No 30002) and our Viability/Cytotoxicity Assay Kit for Bacteria (Cat. No. 30027).

We also offer Ethidium Homodimer III, 1 mM solution in DMSO (catalog no. 40051).

EthD-III is dead cell specific in all cell types, including mammalian cells, bacteria and yeast. See our Cellular Stains Table for more information on how our dyes stain various organisms.