fura2 am

Fura-2 AM is a membrane-permeable Ca²⁺ (calcium ion) indicator that is converted to Fura-2 by esterase within cells. Its fluorescence emission wavelength is around 510 nm, with excitation maxima at 340 nm under high calcium concentrations and 380 nm under low calcium concentrations. Calcium ion concentrations can be calculated using the fluorescence intensity ratio.

Mag-Fura-2 AM, a cell-permeable fluorescent compound, serves as a selective indicator for magnesium ions (Mg2+), demonstrating significant preference for Mg2+ over other bivalent ions including zinc (Zn2+), copper (Cu2+), and calcium (Ca2+). It notably exhibits over 13,000-fold greater selectivity for Mg2+ compared to Ca2+ (Mg2+Kd = 1.9 nM vs. Ca2+Kd = 25 μM). The excitation and emission peak wavelengths are 369 nm and 511 nm, respectively. Further, Mag-Fura-2 AM is utilized as an indirect measure of ATP consumption or production due to its magnesium ion sensitivity.