Trypan blue is commonly used in microscopy (for cell counting) and in laboratory mice for assessment of tissue viability:

• Live cells or tissues with intact cell membranes are not colored by trypan blue.
• Upgraded alternatives are less toxic to cells, have better water solubility, and can present more clear cell images. They can also be used to prevent florescent dyes from leaking out of cells.
• Cell suspensions assayed with trypan blue ideally display two readouts—live-cell populations with clear cytoplasms and blue-stained dead cell populations.

AAT Bioquest has developed multiple Trypan Blue derivatives that are significantly less cytotoxic (leading to more dependable results) as well as kits and supplies for other cell viability tests.  The trypan blue derivatives, Trypan UltraBlue™, Trypan Purple™, and Trypan Red Plus™ , are less toxic and analogous in utility. Trypan UltraBlue™, Trypan Purple™, and Trypan Red Plus™ are highly purified and can be used up to 0.5 mM, 0.75 mM, or 1 mM, respectively, with minimal cell cytotoxicity.