AAT Bioquest

Is Calcein, AM toxic to cells?

Posted August 30, 2021


Calcein, AM is a cell-permeant dye principally used for determining cell viability. Once inside the cell, non-fluorescent Calcein, AM is hydrolyzed by non-specific intracellular esterases into a green fluorescent Calcein dye, which is negatively charged and well-retained within the cytoplasm. Calcein, AM has been used for studies of enzymatic activity, cell membrane integrity, and long-term cell tracking due to its low cellular toxicity. 

It is important to note that for certain cell lines and experimental conditions, relatively high concentrations of Calcein, AM can be toxic to cells.

  • For fluorescence-based imaging we recommended the final concentration of Calcein, AM be 4 to 5 µM (with culture medium) or 2 µM (in HHBS buffer or buffer of your choice with culture medium removed).
  • For flow cytometry we recommend the final concentration of Calcein, AM be 500 nM to 1 µM.

The table below shows the range of available Calcein and CytoCalcein™ cell viability dyes, their excitation and emission maxima, and instrument specifications to assist you in selecting the best dye for determining cell viability.

Cat#Product NameEx/Em (nm)Filter SetChannelUnit Size
22007Calcein Blue, AM *CAS 168482-84-6*351/439DAPI Filter SetPacific Blue Channel1 mg
21908Calcein UltraBlue™ AM360/445DAPI Filter SetPacific Blue Channel10 x 50 µg
22012CytoCalcein™ Violet 450 *Excited at 405 nm*405/444DAPI Filter SetPacific Blue Channel1 mg
22013CytoCalcein™ Violet 500 *Excited at 405 nm*417/502DAPI Filter Set
(Violet Filter Set recommended)
AmCyan Channel1 mg
22002Calcein, AM *CAS 148504-34-1*500/520FITC Filter SetFITC Channel1 mg
22003Calcein, AM *UltraPure grade* *CAS 148504-34-1*500/520FITC Filter SetFITC Channel1 mg
22004Calcein, AM *UltraPure grade* *CAS 148504-34-1*500/520FITC Filter SetFITC Channel20 x 50 µg
21905Calcein UltraGreen™ AM496/524FITC Filter SetFITC Channel10 x 50 µg
22009Calcein Orange™ diacetate530/544TRITC Filter SetPE Channel1 mg
21900Calcein Red™ AM562/576TRITC Filter SetPE Channel1 mg
21902Calcein Deep Red™642/663Cy5 Filter SetAPC Channel1 mg
22011Calcein Deep Red™ AM ester642/663Cy5 Filter SetAPC Channel1 mg
Additional resources

Calcein AM

Cell Viability Probes