离子色谱法测定复方氨基酸（15）双肽（2）注射液中柠檬酸含量

目的：建立测定复方氨基酸（15）双肽（2）注射液中柠檬酸含量的离子色谱法。方法：采用IonPac^TM AS11-HC色谱柱，流动相为氢氧化钾溶液，采用梯度洗脱，流速为1.0 mL&#183;min^-1，柱温为35℃，进样量为20 μL，以带DIONEX AERS 500 4-mm抑制器的电导检测器进行检测。结果：SO₄^2-色谱峰与SO₃^2-色谱峰分离度良好，柠檬酸的质量浓度线性范围为3.945~63.13 μg&#183;mL^-1（r=0.999 5，n=5）；精密度、稳定性、重复性试验的RSD<2%；加样回收率为102.4%，rsd为0.35%（n=9）。测定A、B厂家样品共5批，结果A厂家2批样品中柠檬酸含量分别为184.4、182.1 μg&#183;mL^-1，B厂家3批样品中柠檬酸含量分别为2 264、2 343、2 190 μg&#183;mL^-1。结论：建立的离子色谱法可用于复方氨基酸（15）双肽（2）注射液中柠檬酸的含量测定。

Objective: To establish a new method for determination of citric acid in compound amino acid(15) peptide(2) injection by ion chromatography. Methods: The analytical column was Dionex IonPac^TM AS11-HC (250 mm&#215;4 mm) with an IonPac^TM AG11-HC(50 mm&#215;4 mm) guard column. Gradient KOH solution elute generated by an eluent generator cartridge was used as mobile phase at the flow rate of 1.0 mL&#183;min^-1. The detection was performed by a Dionex suppressed(DIONEX AERS 500 4-mm) conductivity detector. The injection volume was 20 μL and column temperature was 35℃. Results: The linear range of citric acid was 3.945-63.13 μg&#183;mL^-1(r=0.999 5,n=5). RSDs of presion,stability and reproducibility tests were all lower than 2%. The average recovery was 102.4%(RSD=0.35%,n=9). The results showed that the citric acid content of two batches of samples from manufacturer A were 184.4 and 182.1 μg&#183;mL^-1,respectively. The citric acid contents of three batches of samples from manufacturer B were 2 264,2 343 and 2 190 μg&#183;mL^-1. Conclusions: The established method can be used for the determination of citric acid in compound amino acid(15) peptide(2) injection.