DAR-1 / 4,5-Diamino-rhodamine B

3-Amino-4-(N-methylamino)-2',7'-difluorofluorescein diacetate. DAF-FM DA is an important reagent for quantification of low concentrations of nitric oxide in solution. This compound is essentially nonfluorescent until it reacts with NO to form a fluorescent benzotriazole. DAF-FM DA has an excitation/emission maxima of 495nm. DAF-FM Specifications:• Ex/Em of DAF-FM: ~495/515 nm• Lyophilized product should be dissolved using DMSO and then added to an aqueous buffer to create a working solution. • DAF-FM diacetate is cell permeant and passively diffuses across cellular membranes; once inside the cell, it is converted to a cell-impermeant form! • Buffers containing bovine serum albumin (BSA) and phenol red may affect the fluorescence and should be used with caution.• The fluorescence quantum yield of DAF-FM is ~0.005, but increases about 160-fold, to ~0.81, after reacting with NO. Important Advantages of DAF-FM over DAF-2The spectra of the NO adduct of DAF-FM are independent of pH above pH 5.5. Also, the NO adduct of DAF-FM is significantly more photostable than that of DAF-2 >, which means additional time for image capture. Finally, DAF-FM is a more sensitive reagent for NO than is DAF-2 (NO detection limit for DAF-FM ~3nM versus ~5nM for DAF-2).

DAF-2 (4,5-Diaminofluorescein) shows higher photostability than the classical fluorescein derivative DAF. Applications: DAF-2 is highly sensitive reagent for NO detection and determination of nitric oxide synthase activity. DAF-2, however, remains essentially nonfluorescent until it reacts with the nitrosonium cation (produced by spontaneous oxidation of nitric oxide) to form a fluorescent heterocycle, which becomes trapped in the cell's cytoplasm. This sensitive fluorescent probe has been used to identify individual nitric oxideproducing neurons in brain slices, in mitochondria and in living plant cells. In the cell, the product reacts rapidly with NO in the presence of O2 to form the highly fluorescent compound triazolofluorescein (DAF-2T (Cat-No. S5442 >)). References: (1) M. Kirsch et al.; J. Pineal Res. 40(1), 10 (2006), (2) V.M. Dirsch et al.; Biol. Proc. Online 5(1), 136 (2003), (3) N. Nagata et al.; J. Biochem. 125(4), 658 (1999), (4) H. Kojima et al.; Chem. Pharm. Bull. 46, 373 (1998), (5) H. Kojima et al.; Anal. Chem. 70, 2446 (1998)

DAR-1T is for fluorescent detection. It is used as a reference compound for the flourescent (nitric oxide) NO probe DAR-1.Synonyms: Diaminorhodamine-1T

3-Amino-4-(N-methylamino)-2',7'-difluorofluorescein diacetate. DAF-FM DA is an important reagent for quantification of low concentrations of nitric oxide in solution. This compound is essentially nonfluorescent until it reacts with NO to form a fluorescent benzotriazole. DAF-FM DA has an excitation/emission maxima of 495nm. DAF-FM Specifications:• Ex/Em of DAF-FM: ~495/515 nm• Lyophilized product should be dissolved using DMSO and then added to an aqueous buffer to create a working solution. • DAF-FM diacetate is cell permeant and passively diffuses across cellular membranes; once inside the cell, it is converted to a cell-impermeant form! • Buffers containing bovine serum albumin (BSA) and phenol red may affect the fluorescence and should be used with caution.• The fluorescence quantum yield of DAF-FM is ~0.005, but increases about 160-fold, to ~0.81, after reacting with NO. Important Advantages of DAF-FM over DAF-2The spectra of the NO adduct of DAF-FM are independent of pH above pH 5.5. Also, the NO adduct of DAF-FM is significantly more photostable than that of DAF-2 >, which means additional time for image capture. Finally, DAF-FM is a more sensitive reagent for NO than is DAF-2 (NO detection limit for DAF-FM ~3nM versus ~5nM for DAF-2).

4,5-diaminofluorescein diacetate (DAF-2 DA) is a highly sensitive probe for the real time detection of NO in vivo. Cell permeable. Application: DAF-2 DA is probably the most successful indicator for nitric oxide. As with other fluorescein diacetates, DAF-2 diacetate is membrane permeant and is deacetylated by intracellular esterases to 4,5-diaminofluorescein (DAF-2). Can be used for the fluorimetric detection of nitric oxide and in fluorescence microscopy to measure realtime changes in nitric oxide levels in vivo. References: V.M. Dirsch et al.; Biol. Proc. Online 5, 136 (2003)N. Nagata et al.; J. Biochem. 125(4), 658 (1999)H. Kojima et al.; Anal. Chem. 70(13), 2446 (1998) H. Kojima et al.; Chem. Pharm. Bull. 46, 373 (1998) H. Kojima et al.; Neuroreport 9, 3345 (1998)