微乳液相色谱法同时测定白术中白术内酯Ⅰ、Ⅲ的含量

目的：建立一种新的、稳定的微乳体系，并应用微乳液相色谱法同时测定白术药材中白术内酯Ⅰ、Ⅲ的含量。方法：考察影响分离的主要因素：表面活性剂、助表面活性剂、油相、pH、温度、色谱柱等，得到微乳体系为3.3%（w/v）十二烷基硫酸钠-8.25%（v/v）正丁醇-1.15%（v/v）正辛烷，色谱柱为Welch MaterialsXB-C₈（4.6 mm×200 mm，30 μm），流速为1 mL·min^-1，检测波长为220 nm，柱温为20℃。结果：白术内酯Ⅰ、Ⅲ在18 min内达到基线分离，白术内酯Ⅰ的线性范围为2.50～20.1 μg·mL^-1（r²=0.999 2），平均回收率（n=5）为97.89%（RSD=2.42%）；白术内酯Ⅲ的线性范围为3.15～25.2 μg·mL^-1（r²=0.999 3），平均回收率（n=5）为98.61%（RSD=2.19%）；检出限（LOD）分别为1.15、1.36 ng。对5个产地白术药材进行含量测定，得白术内酯Ⅰ的含量范围为0.106～0.217 mg·g^-1，白术内酯Ⅲ的含量范围为0.169～0.389 mg·g^-1。通过优化最终微乳流动相的有机试剂（SDS、正丁醇、正辛烷）含量仅为12.7%。结论：经方法学验证，本法可用于白术药材中白术内酯Ⅰ、Ⅲ的质量分析。与传统HPLC法相比，MELC法采用微乳为流动相，既节约了有机试剂的用量，又减少了有机试剂的排放，具有绿色、经济的优点。

Objective: To develop a novel method of microemulsion liquid chromatography (MELC) for separation and determination of atractylenolide Ⅰ and atractylenolide Ⅲ in Atractylodis Macrocephalae Rhizoma.Methods: The effects of operating factors on the separation selectivity were investigated.Factors,such as surfactant,co-surfactant,oil,chromatography column,temperature and pH,were found to affect separation selectivity.The optimized microemulsion system consisted of 3.3%(w/v) sodium dodecyl sulfate -8.25% (v/v) n-butanol-1.15% (v/v) n-octane.The samples were separated on a Welch Materials XB-C₈ (4.6 mm×200 mm,30 μm) column at 20℃ using a flow rate of 1 mL·min^-1,and the detection wavelength was 220 nm.Results: The linear ranges of atractylenolide Ⅰ and atractylenolide Ⅲ were 2.50-20.1 μg·mL^-1 and 3.15-25.2 μg·mL^-1,with their correlation coefficients (r²) of 0.999 2 and 0.999 3,respectively.The mean recoveries(n=5) were 97.89%(RSD=2.42%) and 98.61%(RSD=2.19%),respectively.The detection limits of detection (LOD) were 1.15 and 1.36 ng,respectively.The quality of the Atractylodis Macrocephalae Rhizoma which were produced in five different places was evaluated by assaying the content of atractylenolide Ⅰ and atractylenolide Ⅲ in them.The atractylenolide Ⅰ ranged in 0.106-0.217 mg·g^-1.The content of atractylenolide Ⅲ ranged in 0.169-0.389 mg·g^-1.The content of organic solvents in the microemulsion mobile phase was very low (12.7%).Conclusion: It is proved by methodology validation that this method can be used for the determination of atractylenolide Ⅰ and atractylenolide Ⅲ in Atractylodis Macrocephalae Rhizoma.With the microemulsion mobile phase,it will greatly reduce pollution,increase productivity,as well as cut down the cost.In addition,it has the advantages of both energy saving and environment protection.