Erythrosin B: the safe trypan blue for cell counting

Although trypan blue is the most common used dye for cell counting, it is more harmful than you think. Time to take some action, for the sake of your own health…

When you say ‘cell counting’ you think ‘trypan blue’. It is the most common used dye in research labs to assess cell viability. Trypan blue is an impermeable dye that cannot pass the intact cell membrane of living cells, in contrast to dead cells’ membranes. It has been widely used in manual cell counting for decades and included in automatic cell counting the past years.

Let’s go back 50 years: trypan blue is a teratogen!

Already in 1968, the teratogenic effects of trypan blue in mice were discovered: that’s almost 50 years ago! However, it has also been already 20 years that alternatives for trypan blue in manual cell counting have been proposed. So why is it that we still use this harmful dye for our cell maintenance, - expansion and experimental setups?

Trypan blue in automatic cell counting

Whereas manual cell counting is still one of the most used methods for cell viability assessment, automatic cell counting turns out to save you time and provides you with more consistent results. Since trypan blue is used with bright-field optics, the most common optics used in automated cell counters, automatic cell counting is optimized for use with this harmful dye.

More recently, automatic cell counters that include more advanced optics, like the LUNA II from Logos Biosystems, have been introduced. Due to this feature, also other, and safer, dyes are feasible for automatic cell counting.

In a comparison study with the LUNA II, the safer option erythrosine B shows similar results compared to trypan blue. As erythrosine B is known as a food coloring product, it is approved by the FDA, thus stated safe.

You need to count your cells; you don’t need trypan blue

Don’t risk your health any longer and get rid of trypan blue: you don’t need it! And whereas cell counting is a necessity, consider saving your time while you’re on it and combine a safer dye like erythrosine B with the LUNA II.

p.s. Also for manual cell counting, erythrosine B is preferable over trypan blue. So why keep using trypan blue and risk your health?