化妆品中苯氧异丙醇2种含量测定方法的比较研究

目的 采用气相色谱法和高效液相色谱法测定化妆品中苯氧异丙醇的含量，探讨使用气相色谱法测定化妆品中苯氧异丙醇含量的可行性。方法 气相色谱法采用火焰离子化检测器（flame ionization detector，FID）进行测定，使用DB-SELECT 624UI石英毛细管柱（60 m×0.32 mm，1.8 mm），载气为高纯氦气，流量1.5 mL·min^-1，进样量1 mL，分流比5∶1，进样口温度为250℃；柱升温程序：初始温度65℃，以20℃·min^-1的速率升到165℃，保持25 min，再以20℃·min^-1的速率升到230℃，保持5 min；火焰离子化检测器温度为260℃。高效液相色谱法采用《化妆品安全技术规范》2015年版防腐剂检验方法项下苯氧异丙醇测定法。结果 2种测定方法测定结果无显著性差异，其中苯氧异丙醇在所建立的气相色谱条件下能与杂质完全分离，分离度>1.5，理论板数>10 000；在1~200 mg·mL^-1线性关系良好（相关系数r为0.999 9）；定量限为1.0 μg·mL^-1；检测限为0.3 μg·mL^-1；平均回收率为84.8%~101.4%；苯氧异丙醇在24 h内稳定性良好。结论 本实验所建立的气相色谱法，可用于化妆品中苯氧异丙醇含量的测定。

Comparison Between the Two Methods of Determining for the Content of Phenoxyisopropanol in Cosmetics

OBJECTIVE To determine the content of phenoxyisopropanol in cosmetics by GC and HPLC, to explore the feasibility of GC for determination of phenoxyisopropanol in cosmetics. METHODS GC was determined by using flame ionization detector(FID) with DB-SELECT 624UI capillary column(60 m×0.32 mm, 1.8 μm). The high purity helium was used as the carrier gas with the flow of 1.5 mL·min^-1. The injection volume was 1 mL with the split ratio of 5:1. The injection temperature was 250℃. The column temperature program:initial temperature 65℃, the temperature was raised to 165℃ at the rate of 20℃·min^-1, kept 25 min, then the temperature was raised to 230℃ at the rate of 20℃·min^-1, kept 5 min. The detector temperature of flame ionization detector(FID) was 260℃. The HPLC for the determination of phenoxyisopropanol adopted the 2015 edition of the Safety and Technical Standards for Cosmetics. RESULTS There was no significant difference between the two methods, phenoxyisopropanol could be completely separated from impurities under established GC conditions, the resolution was >1.5, the number of theoretical plate was >10 000; the linear relationship was good in the concentration range of 1-200 mg·mL^-1(r=0.999 9); the limit of quantification was 1.0 mg·mL^-1; the limit of detection was 0.3 mg·mL^-1; the average recoveries were within 84.8%-101.4%; phenoxyisopropanol kept stable within 24 h. CONCLUSION GC established can be used to determine the phenoxyisopropanol content of cosmetics.