DAF 2DA (DAF-2DA)

DAF-2 diacetate is a sensitive fluorescent indicator for the detection and bioimaging of nitric oxide (NO).^1,2 It is a cell-permeable derivative of DAF-2. Upon entry into the cell, DAF-2 diacetate is transformed into the less cell-permeable DAF-2 by cellular esterases thus preventing loss of signal due to diffusion of the molecule from the cell. In the presence of oxygen, DAF-2 reacts with NO to yield the highly fluorescent triazolofluorescein (DAF-2T). Fluorescence is monitored using excitation and emission wavelengths of 485 and 538 nm, respectively.² At neutral pH the detection limit for NO is 2-5 nM. DAF-2 diacetate can be utilized in cells which produce small amounts of NO, such as endothelial cells, as well as in cells which generate large amount of NO, such as macrophages.^1,2

1.Kojima, H., Sakurai, K., Kikuchi, K., et al.Development of a fluorescent indicator for nitric oxide based on the fluorescein chromophoreChem. Pharm. Bull. (Tokyo)46(2)373-375(1998) 2.Nakatsubo, N., Kojima, H., Kikuchi, K., et al.Direct evidence of nitric oxide production from bovine aortic endothelial cells using new fluorescence indicators: DiaminofluoresceinsFEBS Lett.427(2)263-266(1998)