A method for quantitative analysis of saturated hydrocarbon mineral oil (MOSH) in edible vegetable oil by solid phase extraction (SPE) combined with programmed temperature vaporizer-gas chromatography--flame ionization detection (PTV-GC-FID) was established.The samples were extracted by isooctane,purified with the molecular sieve-silver nitrate silica gel SPE column,concentrated by nitrogen,injected into the GC analysis by large volume injection,separated by the capillary columns of DB-1,determined by a flame photometric detector and quantified by external standard method.The effects of influencing factors on extraction efficiency were investigated,including packing type,amount of packing and elution volume.Under the optimized experimental conditions,the limits of detection and limits of quantification of this method were 0.3 mg/kg and 1.0 mg/kg.Satisfactory linearity in the ranges of 10.0 ～ 500.0 mg/L was obtained with R2 of 0.9991.The spiked recoveries were in the range of 95.7％ ～ 102.5％ at three spiked levels with the relative standard deviations (RSDs) of 2.64％ ～ 4.93％ (n=6).Ten retailed vegetable oils samples were analyzed with the proposed method,and the concentrations of MOSH were 15.4 ～ 80.7mg/kg.The established method has the advantages of good purification effect,low reagent consumption,low detection limit,which is suitable for the separation and quantification of mineral oil saturated hydrocarbons in edible vegetable oils,which is also has good application value.%建立了固相萃取柱(SPE)结合大体积进样-气相色谱-氢火焰离子检测器(PTV-GC-FID)定量分析食用植物油中饱和烃类矿物油(MOSH)的方法.样品经异辛烷提取,自制分子筛-硝酸银硅胶SPE复合柱净化,氮吹浓缩后用程序升温进样口大体积进样分析,外标法定量.重点考察了填料类型、填料用量、洗脱体积等因素对提取效率的影响.结果表明,在优化的条件下,液体石蜡标准溶液在10.0 ～ 500.0 mg/L范围内呈良好线性关系,R2为0.9991,方法检出限和定量限分别为0.3 mg/kg和1.0 mg/kg,样品在30.0、50.0、100.0 mg/kg3个水平下的加标回收率为95.7％ ～ 102.5％,相对标准偏差(RSD)范围为2.64％ ～ 4.93％.运用本方法对10个市售食用植物油样品进行了测定,MOSH含量在15.4～80.7mg/kg之间.本方法净化效果好、试剂消耗量少、检出限低且分析成本低,适用于食用植物油中饱和烃类矿物油残留的定量分析,具有较好的推广应用价值.
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