目的建立顶空毛细管气相色谱法同时测定蛋黄卵磷脂中乙醇、丙酮残留量的分析方法。方法采用顶空进样毛细管气相色谱法,以正丙醇为内标,键合聚乙二醇(Phenomenex ZB-FFAP)石英毛细管色谱柱;柱升温程序,初始35℃,保持10 min,以25℃/min升至180℃,保持5 min;进样口温度220℃;检测器温度250℃;氮气为载气,流速:1 m L/min;分流进样,分流比5∶1;顶空温度80℃,平衡时间45 min。结果丙酮在25.104-2 510.4μg/m L浓度范围线性关系良好,r^2=0.999 7,最低检测限为20 ng,加样回收率为94.0%-97.7%;乙醇在23.7-2 370μg/m L浓度范围线性关系良好,r^2=0.999 3,最低检测限为0.001 6μg,加样回收率为97.3%-102.9%。结论该方法简便、快速、结果准确,适用于测定蛋黄卵磷脂中丙酮、乙醇残留量。
Objective To establish a head-space capillary GC method for the determination of acetone and ethanol residue in egg yolk lecithin. Methods A GC instrument couple with head-space sampler was used. The separation was carried on an ZB-FFAP capillary column with the oven temperature raised from 35 ℃( 10 min) to 180 ℃( 5 min) at the rate of 40 ℃ /min. The temperature of the injection inlet was 220 ℃ and that of FID was 250 ℃. The carried gas was nitrogen at a rate of 1. 0 m L / min. The split rate was 5 ∶1. The headspace vials were balanced at 80 ℃ for 45 min. Results The linear range of acetone was 25. 104-2 510. 4 μg / m L( r^2= 0. 999 7). The minimum detection concentration was 20 ng. The average recovery was 94. 0%- 97. 7%. The linear range of ethanol was 23. 7- 2 370 μg / m L( r^2= 0. 999 3). The minimum detection concentration was 0. 001 6 μg. The average recovery was 97. 3%-102. 9%. Conclusion The developed method is convenient,reproducible and accurate in the residual solvents analysis of egg yolk lecithin.