A rapid, simple spectrophotometric method for simultaneous detection of nitrate and nitrite

Nitric Oxide. 2001 Feb;5(1):62-71. doi: 10.1006/niox.2000.0319.


Numerous methods are available for measurement of nitrate (NO(-)(3)). However, these assays can either be time consuming or require specialized equipment (e.g., nitrate reductase, chemiluminescent detector). We have developed a method for simultaneous evaluation of nitrate and nitrite concentrations in a microtiter plate format. The principle of this assay is reduction of nitrate by vanadium(III) combined with detection by the acidic Griess reaction. This assay is sensitive to 0.5 microM NO(-)(3) and is useful in a variety of fluids including cell culture media, serum, and plasma. S-Nitrosothiols and L-arginine derivatives were found to be potential interfering agents. However, these compounds are generally minor constituents of biological fluids relative to the concentration of nitrate/nitrite. This report introduces a new, convenient assay for the stable oxidation products of nitrogen oxide chemistry in biological samples.

Publication types

  • Comparative Study

MeSH terms

  • Ethylenediamines
  • Free Radical Scavengers
  • Kinetics
  • Luminescent Measurements
  • Nitrates / blood*
  • Nitrites / blood*
  • Sensitivity and Specificity
  • Spectrophotometry, Ultraviolet*
  • Sulfanilamides
  • Temperature
  • Vanadium / pharmacology


  • Ethylenediamines
  • Free Radical Scavengers
  • Griess reagent
  • Nitrates
  • Nitrites
  • Sulfanilamides
  • Vanadium