Fura-2, AM Ester

Fura-2, AM ester is a ratiometric fluorescent dye that binds to free intracellular calcium, and is the preferred dye for ratiometric imaging microscopy. Fura-2, AM ester is membrane-permeant and thus can be loaded into cells via incubation. Because of the relatively low water solubility of the AM ester, the mild detergent Pluronic F-127 is often used as a dispersing agent to facilitate cell loading. Fura-2, AM ester itself does not bind Ca², but it is readily hydrolyzed to Fura-2 by endogenous esterases once it enters cells. Measure using flow cytometry, fluorescence microscopy, or certain fluoresence microplate readers. Upon calcium binding, the fluorescent excitation maximum of the indicator undergoes a blue shift from 363 nm (Ca²-free) to 335 nm (Ca²-saturated), while the fluorescence emission maximum is relatively unchanged at ~510 nm. </p> A major use of Fura-2 is in drug discovery, for measuring intracellular calcium mobilization after activation of G protein-coupled receptors (GPCRs) and calcium channels. </p> <ul> </p> <li>Light yellow solid soluble in DMSO</li> </p> <li>Store at -20°C and protect from light, especially in solution</li> </p> <li>K_d: 145 nM (22°C in pH 7.2 buffer)</li> </p> <li> lamba; _Ex/ lamba;_Em (no Ca²) = 363/512 nm; lamba; _Ex/ lamba; _Em(high Ca²) = 335/505 nm</li> </p> <li> epsilon; (363 nm, no Ca²) = 27,000 M^-1cm^-1; epsilon; (335 nm, high Ca²) = 35,000 M^-1cm^-1</li> </p> <li>C₄₄H₄₇N₃O₂₄</li> </p> <li>MW: 1001.9</li> </p> <li>[108964-32-5]</li> </p> </ul>