Nitric Oxide Synthase Assay

Diaminofluorescein-2 Diacetate (DAF-2DA) is a non-fluorescent cell permeable reagent that can measure free Nitric Oxide (NO) and nitric oxide synthase (NOS) activity in living cells under physiological conditions. Once inside the cell the diacetate groups on the DAF- 2DA reagent are hydrolyze by cytosolic esterases thus releasing DAF-2 and sequestering the reagent inside the cell. Production of nitric oxide converts the non-fluorescent dye, DAF-2, to its fluorescent triaole derivative, DAF-2T. DAF-2T can be observed by: excitation 488 nm and measuring emission at 515 nm.