ORIGINAL Determination of Nitric Oxide-Derived Nitrite and Nitrate in Biological Samples by HPLC Coupled to Nitrite Oxidation

The Author(s) 2013. This article is published with open access at Springerlink.com Abstract Nitrite and nitrate are main stable products of nitric oxide, a pivotal cellular signaling molecule, in bio-logical fluids. Therefore, accurate measurement of the two ions is profoundly important. Nitrite is difficult to be determined for a larger number of interferences and unstable in the presence of oxygen. In this paper, a simple, cost-effective and accurate HPLC method for the deter-mination of nitrite and nitrate was developed. On the basis of the reaction that nitrite is oxidized rapidly to nitrate with the addition of acidic potassium permanganate, the deter-mination of nitrite and nitrate was achieved by the fol-lowing strategy: each sample was injected twice for HPLC analysis, i.e. the first injection was to measure nitrate, and the second injection was to measure total nitrate includin