Quantitative Determination of Subnanomolar Concentration of Nitrite in Natural Water by High-Performance Liquid Chromatography.

Abstract

A new chromatographic method is presented that successfully
determines nirite in natural water at subnanomolar concentration. The
procedure was based on converting the nitrite to a derivative using 2,4-
dinitro phenyl hydrazine followed by separation using High-Performance
Liquid Chromatography (HPLC). The method is simple, rapid, and
requires minimal sample preparation. The 2,4-dinitro phenyl azide
formed is stable for at least 5 weeks under cold and dark conditions. The
accuracy of the method was  checked using the standard colorimetric
technique in several natural water types.  The detection limits of nitrite in
three types of natural water were found to range from 0.1 to 0.2, with
relative standard deviations for the complete procedure varying between
4 and 8%. The method has recovery range from 95 to 100% with relative
standard deviations between 2 and 5%.  Applications of the HPLC method
to study the speciation of nitrite in natural waters in Gaza Strip are also
presented.