离子色谱法测定膦甲酸钠注射液含量及有关物质

 目的 建立离子色谱法测定膦甲酸钠注射液含量和有关物质的测定方法。方法 色谱柱为Dionex Ionpac AG₁₈(4 mm×50 mm，13 μm)+AS₁₈(4 mm×250 mm，7.5 μm)，以在线EG发生罐产生KOH作为流动相，梯度洗脱，流速1 mL·min^-1，电导检测，柱温30 ℃。结果 膦甲酸钠线性范围2～100 μg·mL^-1，相关系数r=0.999 8，检出限0.3 μg·mL^-1，杂质亚磷酸根和磷酸根线性范围0.05～2 μg·mL^-1，相关系数分别为r=0.999 9和r=0.999 8。膦甲酸钠日内精密度RSD为0.35%（n=5），日间精密度0.41%（n=5）。平均加样回收率101%。结论 本方法快速、灵敏，专属性强，适用于膦甲酸钠注射液含量及有关物质亚磷酸根和磷酸根的测定。

Determination of Foscarnet Sodium Injection and Its Related Substance by Ion Chromatography

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 ℃. RESULTS The calibration curve of foscarnet sodium was linear between 2-100 μg·mL^-1 (r=0.999 8)， and the calibration curves of the related substances were linear between 0.05-2 μg·mL^-1 (r=0.999 9 and r=0.999 8). 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.