Calcein AM is a cell-permeant dye that can be used to determine cell viability in most eukaryotic cells. In live cells the nonfluorescent calcein AM is converted to a green-fluorescent calcein, after acetoxymethyl ester hydrolysis by intracellular esterases. The acetomethoxy (AM) derivate of calcein (calcein AM) is widely used for labeling live cells as it can be transported through the cellular membrane into live cells. The AM ester groups mask the part of the molecule that chelates calcium. Upon transporting into live cells cellular esterases cut off the AM groups, the molecule binds to calcium within cell (resulting in acquiring strong green fluorescence), and gets trapped inside. As dead cells lack esterases, only live cells are marked. This feature makes it very useful for testing of cell viability and for short-term marking of cells.
Molecular Weight: 994.86
Compared with other live cell-labeling reagents (such as BCECF-AM and carboxy-fluorescein diacetate), calcein-AM is the most suitable fluorescent probe for staining viable cells because of its low cytotoxicity. Calcein does not significantly affect cellular functions such as proliferation or chemotaxis of lymophocyte. In addition, viability assays using calcein are reliable and correlate well with the standard 51Cr-release assay.
It is recommened to prepare and use Calcein, AM stock solution on the same day. However, if stock solutions need to be prepared in advanced we recommend storing the Calcein, AM stock solution as aliquots in tightly sealed vials at -20°C, dessicated and protected from light. Under these conditions, AM esters should be stable for 3 months. 10% Pluronic F-127 stock solution must be stored at room temperature (DO NOT FREEZE) for up to 6 months. 20 mM Probenecid may be stored at -20°C and protected from light for up to 6 months. Avoid repeated freeze-thaw cycles.
Celltechgen provides high-quality reagents and materials for research use only. For proper handling of potentially hazardous chemicals, please request the Safety Data Sheet (SDS) provided for the product.