10x50 µg. Ex: 492 nm. Em: 514 nm. Soluble in: DMSO. Calbryte(TM) 520, AM is a new fluorescent and cell-permeable calcium indicator. Like other dye AM cell loading, Calbryte(TM) 520 AM ester is non-fluorescent and once gets inside cells, it is hydrolyzed by intracellular esterase and gets activated. The activated indicator is a polar molecule that is no longer capable of freely diffusing through cell membrane, essentially trapped inside cells. Upon binding Ca2+ ions, Calbryte(TM) 520 produces bright fluorescence signal with extremely high signal/background ratio. In addition, Calbryte(TM) 520 demonstrates greatly improved intracellular retention. It has the identical excitation and emission wavelength as Fluo-4, thus the same Fluo-4 assay settings can be readily applied to Calbryte(TM) 520-based calcium assays. Calbryte(TM) 520 is a new generation of fluorescent indicators for the measurement of intracellular calcium. Its greatly improved signal/background ratio and intracellular retention properties make Calbryte(TM) 520 AM the most robust indicator for evaluating GPCR and calcium channel targets as well as for screening their agonists and antagonists in live cells.