Title: Fura-2
CAS Registry Number: 96314-98-6
CAS Name: 2-[6-[Bis(carboxymethyl)amino]-5-[2-[2-[bis(carboxymethyl)amino]-5-methylphenoxy]ethoxy]-2-benzofuranyl]-5-oxazolecarboxylic acid
Molecular Formula: C29H27N3O14
Molecular Weight: 641.54
Percent Composition: C 54.29%, H 4.24%, N 6.55%, O 34.91%
Literature References: Fluorescent calcium imaging agent; structurally related to BAPTA, q.v. Ca2+ binding causes a spectral shift to shorter wavelengths; ratio of the fluorescence at each wavelength is related to changes in Ca2+ binding and is independent of dye concentration. Also used as pentaacetoxymethyl ester, Fura-2/AM, to enhance crossing of membranes. Prepn: G. Grynkiewicz et al., J. Biol. Chem. 260, 3440 (1985). Binding kinetics to Ca2+: A. P. Jackson et al., FEBS Lett. 216, 35 (1987). Determn of Kd: D. L. Groden et al., Cell Calcium 12, 279 (1991). Spectra of intracellular forms: C. S. Owen, ibid. 385. Photophysics: V. Van den Bergh et al., Biophys. J. 68, 1110 (1995). HPLC determn: M. Castle, E. Neuteboom, J. Chromatogr. A 696, 93 (1995). Determn in tissue: N. N. P. Tran et al., Cell Calcium 18, 420 (1995). Practical aspects of use in intracellular Ca2+ measurement: K. R. Sipido, G. Callewaert, Cardiovasc. Res. 29, 717 (1995).
Properties: uv max absorption (100 mM KCl): 362 nm free dye; 335 nm Ca2+ complex. emission max: 512 nm free dye; 505 nm Ca2+ complex.
Absorption maximum: uv max absorption (100 mM KCl): 362 nm free dye; 335 nm Ca2+ complex
Use: Fluorescent probe for measurement of calcium in biological systems.
Furaltadone Furametpyr Furan Furazabol Furazolidone

CAS number 113694-64-7 YesY
PubChem 57054
ChemSpider 51442 YesY
Jmol-3D images Image 1
Molecular formula C29H22N3O145-
Molar mass 636.50 g/mol
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Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Fura-2, an aminopolycarboxylic acid, is a ratiometric fluorescent dye which binds to free intracellular calcium.[1] It was the first widely used dye for calcium imaging, and remains very popular. Fura-2 is excited at 340 nm and 380 nm of light, and the ratio of the emissions at those wavelengths is directly correlated to the amount of intracellular calcium. Regardless of the presence of calcium, Fura-2 emits at 510 nm of light. The use of the ratio automatically cancels out confounding variables, such as variable dye concentration and cell thickness, making Fura-2 one of the most appreciated tools to quantify calcium levels. More recently, genetically-encoded calcium indicators based on spectral variants of the green fluorescent protein, such as Cameleons,[2] have supplemented the use of Fura-2 and other small molecule dyes for calcium imaging.