气相色谱法测定鱼油软胶囊中二十碳五烯酸和 二十二碳六烯酸的柱前衍生化方法改进

Improvement of pre-column derivatization for the determination of eicosapentaenoic acid and docosahexaenoic acid in fish oil soft capsules by gas chromatography

中文关键词:  二十碳五烯酸  二十二碳六烯酸  柱前衍生化  气相色谱法  保健食品

英文关键词:eicosapentaenoic acid  docosahexaenoic acid  pre-column derivatization  gas chromatography  health food

中文摘要:

      目的 建立柱前衍生-气相色谱法测定保健食品中二十碳五烯酸(eicosapentaenoic acid, EPA)和二十二碳六烯酸(docosahexaenoic acid, DHA)含量的分析方法。方法 鱼油软胶囊经皂化后用1%的硫酸-甲醇甲酯化, 用气相色谱法测定, FID检测器检测, 色谱柱为DB-FFAP(30 m×0.25 mm, 0.25 ?m), 进样口温度250 ℃, 检测器温度260 ℃, 柱温215 ℃, 直接进样, 外标法定量。结果 EPA和DHA在0.05~5 mg/mL范围内线性良好(rEPA=0.9999, rDHA=0.9999), EPA和DHA的回收率分别为93.1%~102.3%和92.2%~103.9%, EPA和DHA的相对标准偏差均小于3%。结论 该方法操作简便、快捷, 避免了有毒试剂的使用, 定量准确, 重现性好, 适合大批量样品的快速检测。

英文摘要:

      Objective To establish a rapid method for the determination of the content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in health food by gas chromatography with pre-column derivatization. Methods Fish oil soft capsules were esterified with 1% sulfuric acid-methanol after saponification and then analyzed by gas chromatography coupled with flame ionization detector (FID). This method was performed by direct injection of sample via analytical column, DB-FFAP (30 m×0.25 mm, 0.25 ?m) under injector temperature of 250 ℃, detector temperature of 260 ℃, and column temperature of 215 ℃. The sample was quantified by external standard method. Results Both EPA and DHA had a good linearity in range of 0.05~5 mg/mL (rEPA=0.9999, rDHA=0.9999). The recoveries of EPA and DHA were 93.1%~102.3% and 92.2%~103.9%, respectively, while the relative standard deviations of EPA and DHA were 1.85% and 1.09%, respectively. Conclusions This method is accurate, simple, and high-efficiency in determination of EPA and DHA simultaneously without using toxic reagents. The procedure can be easily transferred to determine EPA and DHA in large number of samples.