Definition: A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays.
calcein AM [ 4',5'-bis(N,N-bis(carboxymethyl)aminomethyl)fluorescein acetoxymethyl ester,calcein-AM,calcein-acetoxymethyl ester ] a non-fluorescent compound cleaved to a fluorescent compound by non-specific intracellular esterases