Nitrite exists widely in water and soil, which is an important intermediate of organic nitrogen
decomposition. It may cause cancer of digestive system if intake too much.
In acidic condition, nitrite is reacted with aminobenzene sulfonic acid to form diazo-compound, then the
compound is reacted with N-1-naphthylethylenediamine dihydrochloride to form purple-red azo
compound, which can be detected by colorimetric assay at 540 nm.
Reagents and Equipments Required but Not Provided:
Spectrophotometer, analysis balance, centrifuge, 1 mL glass cuvette and distilled water.
