Determination of nitrite in salted fish by improved ion chromatography

We determined the nitrite in salted fish by an improved ion chromatography method. The samples were first pretreated by AgNO3 solution to remove most of the Cl- and the rest of Cl- was excluded by using the Anpelclean TMIC-Ag column. Then the separation of nitrite was determined by suppressed conductivity detection on Ion Pac AS23 (4 mm250 mm) analytical column and Ion Pac AG23 (4 mm50 mm) guard column using 4.5 mmolL-1 NaCO3 and 0.8 mmolL-1 NaHCO3 as elution solvents at a flow rate of 1.0 mLmin-1. The linear range of this improved method is 0.01~2.00 mgL-1 with correlation coefficient (R) of 0.999 9; the detection limit is 0.2 mgkg-1 and the recovery is 83.0%~101.6%. The method with simple and fast pretreatment can determine nitrite in salted fish products more accurately.