手性液相色谱法直接定量乳粉中RRR-α-生育酚

Direct quantification of RRR-α-tocopherol in milk powder by chiral liquid chromatography

中文关键词:  RRR-α-生育酚  维生素E  手性  液相色谱法  乳粉

英文关键词:RRR-α-tocopherol  vitamin E  chiral  liquid chromatography  milk powder

中文摘要:

      目的 建立手性液相色谱法直接测定乳粉中RRR-α-生育酚的检测方法。方法 样品经氢氧化钾皂化, 石油醚-异丙醚萃取。经小粒径纤维素衍生物型手性柱Daicel Chiralcel OD-3 (2.1 mm×150 mm, 3 μm)直接分离, 采用无水乙醇-正己烷(5:995, V:V) (A)和三乙胺-正己烷(5:995, V:V) (B) (A:B=10:90)作为流动相进行等度洗脱, 流速为0.2 mL/min, 柱温30 ℃, 检测波长为294 nm, 外标法定量。结果 RRR-α-生育酚和其他α-生育酚异构体的分离度大于1.2。在0.5~50 μg/mL范围内线性关系良好, 相关系数大于0.999, 检出限为0.20 mg/100 g, 定量限为0.60 mg/100 g, 加标回收率为95.0%~109.4%, 相对标准偏差为2.7%。结论 该方法快速、准确、灵敏, 适合测定乳粉中RRR-α-生育酚的含量。

英文摘要:

      Objective To establish a method for directly determining RRR-α-tocopherol in milk powder by chiral liquid chromatography. Methods The samples were saponified with potassium hydroxide and extracted with petroleum ether-isopropyl ether. DAICEL Chiralcel OD-3 (2.1 mm×150 mm, 3 μm) was directly separated on a small particle size cellulose derivative chiral column, and isocratic elution was performed using absolute ethanol-n-hexane (5:995, V:V) (A) and triethylamine-n-hexane (5:995, V:V) (B) (A:B=10:90) as the mobile phases, with the flow rate of 0.2 mL/min, the column temperature of 30 ℃, the detection wavelength of 294 nm, and the quantification by external standard method. Results The resolutions of RRR-α-tocopherol and other α-tocopherol isomers were greater than 1.2. The linearities were good within the range of 0.5?50 μg/mL, with the correlation coefficient greater than 0.999. The limit of detection was 0.20 mg/100 g, and the limit of quantitation was 0.60 mg/100 g. The recoveries after standard addition were 95.0%?109.4%, and the relative standard deviation was 2.7%. Conclusion This method is rapid, accurate and sensitive, and is suitable for the determination of RRR-α-tocopherol in milk powder.