Determination of foscarnet sodium injection and its related substance by ion chromatography / 中国药学杂志

ABSTRACT

OBJECTIVE: To establish a gradient ion chromatography method to determine the content of foscarnet sodium injection and its related substances. METHODS: The separation was performed on an Ionpac AG18 (4 mm×50 mm, 13 μm) + AS18 column (4.0 mm×250 mm, 7.5 μm) using potassium hydroxide produced by eluent generator (EG) as the mobile phase at a flow rate of 1 mL · min-1. Suppressed conductivity detection was adtopted. The column temperature was maintained at 30°C. RESULTS: The calibration curve of foscarnet sodium was linear between 2-100 μg · mL-1 (r=0.9998), and the calibration curves of the related substances were linear between 0.05-2 μg · mL-1 (r=0.9999 and r=0.9998). The intra-day and inter-day RSDs of foscarnet sodium were 0.35% (n=5) and 0.41% (n=5), respectively. The average recovery was 101%. CONCLUSION: The method is specific, sensitive and can be applied to determine the content and impurities of foscarent sodium injection.