The Calcein AM Cell Viability Assay Kit is designed to quantify live cell numbers based on their endogenous esterase activity and plasma membrane integrity.

• Quantitate live cells using green fluorescence
• 30-min assay
• True endpoint viability assay; only live cells retain signal
• For fluorescence microplate reader, fluorescence microscopy, or flow cytometry
• Ex/Em 485/530 nm

Calcein AM is a widely used green fluorescent cell marker. Calcein AM is itself non-fluorescent and membrane-permeant, and thus can be introduced into cells via incubation. Once inside the cells, endogenous esterases hydrolyze the compound into the highly negatively charged green fluorescent dye calcein, which is retained in the cytoplasm in live cells. Only viable cells with intact plasma membranes retain fluorescence, making this a true end-point assay for cell viability. The fluorescent signal generated from the assay is proportional to the number of living cells in the sample. Calcein AM is also a useful tool for cell tracing.