真空顶空气相色谱法的研究及其应用

研究了一种新的顶空采样方法--真空顶空法.通过实验,比较了其与加热顶空气相色谱法的优缺点,发现将两种顶空方法联用能取得更好的效果.将这种联用方法应用于食用油中甲醇和6号溶剂油残留量的测定,得到甲醇和6号溶剂油残留的质量浓度与其峰面积线性范围分别为10.0～180 μg/mL、12.0～161 μg/mL,回归方程分别为y=0.031 8x-0.078 3、y=0.056 1x-0.012 5,相关系数为0.999 1;检出限3.3、5.6 μg/mL,RSD为1.90%和3.32%,回收率为 92.0%～106%.

Research and application of vacuum headspace GC

A novel capillary gas chromatography defined as vacuum headspace capillary gas chromatography was developed.Taking into account the advantages and disadvantages of heat headspace GC method and vacuum headspace capillary gas chromatography,it would be beneficial to combine these two methods together.In this study,the combination method was used in detecting the residual amount of methanol and No.6 solvent in edible oil.Under the optimized condition,the linear relationship between the peak area and mass concentration of methanol and No.6 solvent was in the range of 10.0～180 μg/mL,and 12.0～161 μg/mL,respectively,corresponding to a linear regression equation y=0.031 8x-0.078 3 (r=0.999 1) and y=0.056 1x-0.012 5 (r=0.999 1),respectively.Detection limits of the method were found to be 3.3 μg/mL and 5.6 μg/mL,respectively.The RSD were 1.90% and 3.32%,respectively,and the recovery rates were in the range of 92.0%～106%.