For quantitative determination of nitric oxide synthase (NOS) activity and screen for NOS inhibitor. Key Features: Sensitive and accurate. Detection range 0.25 - 25 U/L in 96-well plate. Rapid and reliable. Can be completed in 40 min if reduction of NO<SUB>3</SUB><SUP>-</SUP> to NO<SUB>2</SUB><SUP>-</SUP> is performed at 60°C. Method: OD540nm. Samples: Biological. Species: All. Procedure: Assay takes 40 min. Kit size: 100 tests. Detection limit: 0.25 U/L.