Calcein Blue AM acetate(ab275490)

MW 465.4 Da, Purity >95%. Blue fluorescent cell viability probe which won't overlap with green fluorescence from other probes. Penetrates live cell membranes and is virtually non-fluorescent. Upon ubiquitous esterase enzyme activity it produces a bright blue fluorescent that is trapped in live cells - convenient for measurement by epifluorescence light microscopy or flow cytometry. Useful to measure the total number of live versus dead cells - dye leaks out quickly due to the compromised membrane in dead cells resulting in no staining.