亲水作用色谱法测定左卡尼汀注射液含量及杂质A

Determination of Content and Impurity A of Levocarnitine Injection by Hydrophilic Interaction Liquid Chromatography

通过考察流动相中有机相的比例、缓冲液浓度、pH值、柱温以及流速等因素的影响,建立亲水作用色谱法测定左卡尼汀注射液含量及杂质A的方法.最终确定的色谱条件为采用XBridgeAmide色谱柱(4.6mm×250mm,3.5μm),以缓冲液(10mmol/L乙酸铵,用冰醋酸调节pH值5.0)-乙腈(20∶80)为流动相,柱温40℃,检测波长205nm.经方法学验证,左卡尼汀与杂质A分离度良好(R>1.5),左卡尼汀与杂质A浓度分别在0.530~3.21mg/mL、2.06~82.4μg/mL范围内线性关系良好,平均回收率(n=9)分别为100.4%和101.2%.杂质A检测限(S/N=3)为29.0ng/mL、定量限(S/N=10)为68.7ng/mL.结果表明该法可用于左卡尼汀注射液质量的控制.

A method for the determination of the content and impurity A of levocarnitine injection is developed by hydrophilic interaction liquid chromatography. A number of separation parameters are investigated, including pH value, concentration of the buffer, acetonitrile content, flow rate and column temperature. Finally, the XBridge Amide column （4.6 mm× 250 mm, 3.5 μm） is used with a mobile phase consisting of 10 mmol/L ammonium acetate buffer pre-adjusted to pH value of 5.0 and acetonitrile （20： 80）. The column temperature is 40 ℃ and the detection wavelength is 205 nm. The methodological validation results show that impurity A can be completely sepa- rated from levocarnitine （R 〉 1.5 ）. The calibration curves for levocarnitine and impurity A revealed good lineari- ties in the range of O. 530 - 3.21 mg/mL, 2.06 - 82.4 Fg/mL, respectively. The average recoveries （n = 9） of the above compounds are 100.4% and 101.2%, respectively. The limit of impurity A detection （S/N = 3） is 29.0 ng/mL and quantification （S/N = 10） is 68.7 ng/mL. It is indicated that this established method can be used for the quality control of levocarnitine injection.