目的 建立离子色谱法测定硫酸依替米星注射液中抗氧剂亚硫酸钠含量的方法。方法 采用DionexIonPac AS11-HC(4 mm × 250 mm)色谱柱,DionexIonPac AG11-HC(4 mm × 50 mm)保护柱,以氢氧化钾溶液为淋洗液进行梯度淋洗,流速1.0 mL·min^-1,抑制电流99 mA,电导检测器检测,电导池温度35 ℃,柱温30 ℃。结果 亚硫酸钠在8~80 μg·mL^-1内线性关系良好;检测限为0.02 μg·mL^-1(S/N=3),定量限为0.09 μg·mL^-1(S/N=10)。结论 本实验建立的方法快速、准确、重现性好,有助于制剂中亚硫酸钠的用量控制。亚硫酸钠作为抗氧剂有其使用的合理性,但样品中浓度过高,其处方量尚待进一步研究降低。

OBJECTIVE To establish an ion chromatography method for measuring the content of sodium sulfite as an antioxidant in etimicin sulfate injection. METHODS DionexIonPac AS11-HC (4 mm×250 mm) and DionexIonPac AG1-HC (4 mm×50 mm) were employed as anion analytical column and anion guard column to separate sodium sulfite and determine its content. Gradient elution was carried out with potassium hydroxide solution at the flow rate of 1.0 mL·min^-1. Conductivity detector was used with the suppressor current set at 99 mA, the conductivity pool was maintained at 35 ℃ and the column temperature was maintained at 30 ℃.RESULTS A good linear relationship was found between the peak response and the concentration range of 8-80 μg·mL^-1. The detection limit was determined to be 0.02 μg·mL^-1 (S/N=3), and the quantitation limit was 0.09 μg·mL^-1 (S/N=10). CONCLUSION In this paper, we set up an analytical technique with such characteristics as rapidity, accuracy and reproducibility, which will serve to control the dosage of sodium sulfite. So far, it seems appropriate to use sodium sulfite as an antioxidant, but its amount in pharmaceutical preparations should be further optimized and decreased in the future.