摘要
建立了一种固相萃取（SPE）离线净化,气相色谱（配备大体积进样系统（LVI））定量分析油茶籽油中矿物油污染物（MOSH）的方法。SPE柱采用Ag NO3渍活化硅胶为填料,同时比较了添加活化氧化铝前后的效果,确定SPE柱填料为10 g银渍活化硅胶-10 g活化氧化铝;LVI的程序升温（PTV）参数优化为初始温度75℃保持1 min（分流比200∶1）,以250℃/min升温至370℃（关闭分流阀1 min）;切换分流比为50∶1;进样量40μL。结果表明：MOSH标准液体石蜡在5~500 mg/L范围呈良好线性关系,相关系数为0.998,方法的检出限和定量限分别为0.26 mg/kg和0.80 mg/kg,加标回收率93.3%~112.7%,相对标准偏差（RSD）为1.8%~5.2%,日间和日内重复性（RSD）均小于2.6%。本方法用于市售11个油茶籽油中MOSH含量测定,其结果为6.8~76.7 mg/L。本方法操作简便、检出限低、重现性好且成本低廉,适用于食用油中MOSH的定量分析。
An alternative method based on an off-line solid phase extraction（ SPE） combined with programmable temperature vaporizer-based（ PTV） large volume injection-gas chromatography-flame ionization detection（ LVI-GC-FID） was developed. The goal of this study was to determine mineral oil saturated hydrocarbons（ MOSH） in camellia seed oils. The purification condition of SPE columns with silver impregnated the activated silica gel and activated aluminum oxide was optimized. The optimal SPE cartridge was loaded with 10 g of Ag-activated silica gel per 10 g of activated aluminum oxide. The PTV initial temperature was set at 75℃ for 1 min（ split 200∶ 1）,and heated from 75℃ to 370℃ at 250℃ / min. Then the diverter valve was closed for 1 min and opened again with the split flow ratio changing to 50∶ 1. The injection volume was 40 μL. The calibration curve of paraffin oil was liner in the range of 5-500 mg / kg with correlation coefficient of 0.998. The detection limit（ LOD） and the quantification limit（ LOQ） of paraffin oils in hexane were 0.26 mg / kg and 0.80 mg / kg,respectively. The recoveries from spiked oil samples were between 93.3%and 112.7%,with relative standard deviation（ RSD） of 1. 8%- 5. 2%,the RSD of intra-day and inter-day were less than 2.6%. This procedure was applied to analyze the MOSH in 11 commercial camellia seed oils and the contamination was found to range from 6.8 mg / kg to 76.7 mg / kg. The method is simple in operation with high sensitivity,good reproducibility and low cost,and suitable for determination of MOSH in vegetable oils.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2016年第9期1419-1424,共6页
Chinese Journal of Analytical Chemistry
基金
得到北京市科技计划课题(No.Z161100000616005)
北京市科学技术研究院财政专项(No.PXM2016_178305_000010)的资助
关键词
油茶籽油
矿物油
固相萃取
大体积进样气相色谱仪
氧化铝
Camellia seed oils
Mineral oil saturated hydrocarbons
Solid phase extraction
Large volume injection-gas chromatography
Aluminum oxide
