Simultaneous Determination of Nitrite and Azide Ions in Valsartan.

Abstract

This study aimed to establish an ion chromatography for the simultaneous determination of nitrite and azide ions in valsartan. Dionex IonpacAG18 (4×50mm2) and Dionex IonpacAS18 (4×250mm2) were used as the 2D guard column and analytical column, respectively. Dionex AMGTMC18 (4×30mm2) was used as a 1D pre-separation column and Dionex UTAC-ULP1 as the concentration column. KOH solution generated by an online eluent generator (EG) was used as the 2D mobile phase, and gradient elution was performed at 1mL/min. Water and acetonitrile were used as 1D mobile phase, and gradient elution was performed at 0.5mL/min. Suppressed conductivity detector (suppressor, ASRS 300 4mm) was used for detection. The column temperature was 30°C, while that of the detector was 35°C. This method showed satisfactory reproducibility and recovery. The linear range and the correlation coefficient for both nitrite and azide ions were 0.01-0.2mg/L and 0.9998, respectively. However, the recovery rate was 85-115% for nitrite and 90-110% for azide ions. This method was suitable for the simultaneous determination of nitrite and azide ions in valsartan and other sartan drugs.