随着微乳作为中药提取溶剂的不断探索,聚氧乙烯烯(35)蓖麻油(CrEL),一种常用的表面活性剂,正在被研究人员利用。然而,检测微乳液提取物中这种表面活性剂残留的问题极大地阻碍了微乳液溶剂的进一步发展。基于CrEL中各组分的化学结构及2020年版《中国药典》(Vol.Ⅳ),本研究采用气相色谱法(GC)和单因素实验优化了由CrEL制备蓖麻油酸甲酯的方法。验证了两者之间的转换系数,并采用最佳的样品制备方法对三个批次的泽泻汤微乳提取物进行了加工。测定生成的蓖麻酸甲酯的含量,利用上述换算系数计算泽泻汤微乳提取物中CrEL的含量。结果表明,确定了CrEL的最佳制备方法。具体来说,将10mL的1mol·L〜(-1)KOH-甲醇溶液在60℃水浴中加热15min。随后,将10mL三氟化硼乙醚合甲醇(1∶3)溶液在60℃水浴中加热15min,然后用正己烷萃取两次。CrEL可以稳定生产20.84%的蓖麻酸甲酯。根据这个转换系数,三批泽泻汤微乳提取物中CrEL的平均质量浓度为11.94mg·mL~(-1),与微乳配制过程中CrEL质量浓度11.57mg·mL~(-1)无显著差异,说明本研究建立的含量测定方法具有较高的准确性,敏感,可重复。可用于泽泻汤微乳提取物的后续研究,为其他含CrEL制剂的质量控制提供参考。
With the continuous exploration of microemulsions as solvents for traditional Chinese medicine extraction, polyoxyethy-lene(35) castor oil(CrEL), a commonly used surfactant, is being utilized by researchers. However, the problem of detecting residues of this surfactant in microemulsion extracts has greatly hampered the further development of microemulsion solvents. Based on the chemical structures of the components in CrEL and the content determination method of castor oil in the 2020 edition of the Chinese Pharmacopoeia(Vol. Ⅳ), this study employed gas chromatography(GC) and single-factor experiments to optimize the preparation method of methyl ricinoleate from CrEL. The conversion coefficient between the two was validated, and the optimal sample preparation method was used to process microemulsion extracts of Zexie Decoction from three batches. The content of methyl ricinoleate generated was determined, and the content of CrEL in the microemulsion extracts of Zexie Decoction was calculated using the above conversion coefficient. The results showed that the optimal preparation method for CrEL was determined. Specifically, 10 mL of 1 mol·L~(-1) KOH-methanol solution was heated at 60 ℃ for 15 min in a water bath. Subsequently, 10 mL of boron trifluoride etherate-methanol(1∶3) solution was heated at 60 ℃ for 15 min in a water bath, followed by extraction with n-hexane twice. CrEL could stably produce 20.84% methyl ricinoleate. According to this conversion coefficient, the average mass concentration of CrEL in the three batches of Zexie Decoction microemulsion extracts was 11.94 mg·mL~(-1), which was not significantly different from the CrEL mass concentration of 11.57 mg·mL~(-1) during microemulsion formulation, indicating that the established content determination method of this study was highly accurate, sensitive, and repeatable. It can be used for subsequent research on microemulsion extracts of Zexie Decoction and provide a reference for quality control of other drug formulations containing CrEL.