目的 建立以氢氧根作为淋洗液的离子色谱法测定复方氨基酸注射液（20AA）中醋酸根的方法。方法 使用Dionex ICS 3000离子谱仪，Dionex As19-Ag19阴离子交换色谱柱（250 mm×4 mm），水–30 mmol/L氢氧化钠溶液为淋洗液，梯度洗脱，体积流量1.0 mL/min，柱温30 ℃，进样量20 μL，抑制型电导检测器，检测池温度35 ℃。结果 醋酸根与相邻杂质的分离度为1.8，最低检出浓度0.75 μmol/L，线性范围0.75～2.24 mmol/L（r=0.999 5），平均回收率为100.7%，RSD值为1.7%。结论 该方法操作简单，分离度好，背景低，是控制复方氨基酸注射液（20AA）中醋酸根的可靠方法。

Objective To establish a method for the determination of acetate ion in Compound Amino Acid Injection (20AA) by ion chromatography with hydroxide as mobile phase. Methods Determination was carried out on Dionex As19-Ag19 anion-exchange chromatography column (250 mm × 4 mm) with Dionex ICS 3000 Ion Spectrometer. The elutriant consisted of water-30 mmol/L sodium hydroxide with gradient elution at a flow rate of 1.0 mL/min. The temperature of column was set at 30 ℃ with injection volume of 10 μL. Inhibitory electrical conductivity detector was used with detecting pool temperature of 35 ℃. Results The resolution between acetate ion peak and adjacent peak was 1.8, and LOD was 0.75 μmol/L. The calibration curve was linear in the range of 0.75 — 2.24 mmol/L (r = 0.999 5). The recovery was 100.7% with RSD value of 1.7% (n = 9). Conclusion The method is simple with good resolution and low background, and can be used for quality control of acetate ion in Compound Amino Acid Injection (20AA).