目的建立盐酸麻黄碱(E)和盐酸伪麻黄碱(PE)中杂质的高效液相色谱HPLC测定方法。方法用RPC18色谱柱,以20mmol/LKH2PO4水溶液-甲醇(96:4)为流动相,检测波长为210nm,分析时间为20min。结果6种麻黄生物碱均达到基线分离;混合对照品连续进样6次,色谱峰面积RSD均小于1.0%;对照品质量浓度在选定范围内呈现良好的线性关系(R²>0.999);各成分最低检出限分别为:去甲基麻黄碱(NE)为0.05μg/mL,去甲基伪麻黄碱(NPE)为0.04μg/mL,E和PE为0.1μg/mL,甲基麻黄碱(ME)和甲基伪麻黄碱(MPE)为0.2μg/mL;各成分的加样回收率均大于97.1%;6个待测样品均被检测出不同程度的杂质。结论本方法分离度好、精密度高、专属性强、灵敏度高,可用于麻黄生物碱类药物中杂质成分的定性和定量测定。

Objective To develop an HPLC method for determination of impurities in ephedrine hydrochloride (E) and pseudoephedrine hydrochloride (PE). Methods All of ephedrine alkaloids reference substances and samples were separated with a 20 mmol/L aqueous KH_2PO_4 containing 4% methanol buffer under isocratic elution by using a C_ 18 reversed-phase column within 20 min, and the detection wavelength was 210 nm. Results Six ephedrine alkaloids reference substances were base-line separated and were linear in concentration of selection (R20.999). The relative standard deviation (RSD) of chromatogram area was less than 1.0% for all of them after six successive injections. The detection limit was 0.05 μg/mL for norephedrine (NE), 0.04 μg/mL for norpseudoephedrine (NPE), 0.1 μg/mL for E and PE, and 0.2 μg/mL for mephedrine (ME) and mepseudoephedrine (MPE), respectively (S/N≥3). The recovery rate was more than 97.1% for six ephedrine alkaloids. Under this method system, all of the above-mentioned six samples were tested and found to contain some of the impurity at different levels. Conclusion This developed method, which is very simple, perfect precision, high sensitivity, and selectivity, can be used for the qualitative and quantitative determination of impurities of ephedrine alkaloid-type samples.

科技部重大专项基金资助项目(2002BA906A29-3,2002DEA20021-3,2001BA701A36-18)