高效液相色谱法测定异甘草酸镁原料药中的有关物质

Determination of related substances in magnesium isoglycyrrhizinate by HPLC

目的:建立异甘草酸镁原料药中有关物质的高效液相色谱(HPLC)检查方法。方法:采用Agilent Poroshell 120 C18色谱柱(150 mm×4.6 mm,4μm),以50 mmol·L^-1乙酸铵溶液(含0.2%三氟乙酸,氨水调节pH值至8.0)为流动相A,以50 mmol·L^-1乙酸铵溶液-乙腈(15∶85)为流动相B,梯度洗脱;流速为1.0 mL·min^-1,柱温为35℃,检测波长为250 nm,进样量为10μL。结果:在此色谱条件下,异甘草酸镁与各杂质能完全分离。异甘草酸镁的线性范围为0.33~3.33μg·mL^-1,相关系数为0.999 9,检测限与定量限分别为0.11和0.33μg·mL^-1。各已知杂质在相应浓度范围内均拥有良好的线性关系,相关系数均在0.999 8~0.999 9。加样回收率(n=12)均在90%~108%之间,RSD均<3.0%。结论:本法专属性好,准确度高,能有效检测出异甘草酸镁原料药中的有关物质。

Objective: To establish an HPLC method for determination of related substances in magnesium isoglycyrrhizinate. Methods: Agilent Poroshell 120 C18 column(150 × 4. 6 mm,4 μm) was chosen for analysis.Gradient elution was used to determine the related substances of magnesium isoglycyrrhizinate with 50 mmol·L^-1 ammonium acetate solution(containing 0. 2% TFA,p H adjusted to 8. 0 with ammonia) as mobile phase A and 50 mmol·L^-1 ammonium acetate solution-acetonitrile(15 ∶85) as mobile phase B. The flow rate was 1.0 mL·min^-1,the column temperature was 35℃,the detection wavelength was 250 nm,and the injection volume was 10 μL.Results: The related impurities were completely separated from magnesium isoglycyrrhizinate under the chromatographic conditions. The linear range of the calibration curve for magnesium isoglycyrrhizinate was 0.33 ~3.33 μg·m L-1 with correlation coefficient of 0.999 9,and the detection limit and limit of quantitation were 0. 11 and 0. 33 μg·m L-1,respectively. All known impurities had good linearity in appropriate concentrationranges and the correlation coefficients were all in the range of 0. 999 8 ~ 0. 999 9. The average spiked recovery(n = 12) of all known impurities was in the range of 90% ~ 108%,with RSDs of less 3. 0%. Conclusion: The method is specific and accurate,which can effectively detect related substances in magnesium isoglycyrrhizinate.