正相高效液相色谱法同时测定食用油中生育酚和生育三烯酚的含量

在GB 5009.82—2016《食品安全国家标准食品中维生素A、D、E的测定》第二法和GB/T26635—2011《动植物油脂生育酚及生育三烯酚含量测定高效液相色谱法》两个国标方法的基础上,结合并优化了两个标准中的测定条件,确定了使用硅胶柱同时测定食用油中α-、β-、γ-、δ-生育酚和α-、β-、γ-、δ-生育三烯酚8种异构体的正相高效液相色谱法。结果表明:样品用90%正己烷+10%甲基叔丁基醚-四氢呋喃-甲醇混合液(体积比20∶1∶0.1)为流动相涡旋振荡溶解10 s后,在用流动相平衡90 min以上的硅胶色谱柱上进行分离,经荧光检测器分析,8种异构体在0.2~10μg/m L范围内线性关系良好,相关系数均大于0.99,检出限均为2 mg/kg,定量限均为6 mg/kg,回收率在70.08%~116.33%之间,相对标准偏差为1.14%~9.85%。优化后方法的回收率和重复性得到了提高,分离效果也有很大改善,能满足食用油中生育酚和生育三烯酚含量同时测定的需要。

Simultaneous determination of tocopherol and tocotrienol in edible oil by NP-HPLC

Based on GB 5009. 82—2016 second method and GB/T 26635—2011 two national standard methods,the determination conditions in the two standards were combined and optimized,and the normal phase high performance liquid chromatography( NP-HPLC) detection method for simultaneous determination of α-,β-,γ-,δ-tocopherol and α-,β-,γ-,δ-tocotrienols in edible oil using silica gel column was determined. The results showed that with 90% n-hexane + 10% methyl tert-butyl ether-tetrahydrofuran-methanol mixture( volume ratio 20∶ 1∶ 0. 1) as mobile phase,the sample was dissolved by vortex agitation for 10 s,then separated on a silica gel chromatographic column,which had been equilibrated with mobile phase for more than 90 min,finally analyzed by a fluorescence detector. The linear range of eight isomers was 0. 2-10 μg/m L with the correlation coefficients above0. 99,and the detection limit and quantitation limit were 2 mg/kg and 6 mg/kg respectively. The recovery rates of the eight isomers was 70. 08%-116. 33%,and the relative standard deviation was1. 14%-9. 85%. After optimization,the recovery rate and repeatability of the determination method were improved, and the separation effect was also greatly improved. The method could meet the requirement of simultaneous determination of tocopherol and tocotrienol in edible oil.