腐殖酸磁固相萃取与高效液相色谱-荧光检测联用测定食用油中的苯并芘

采用简单的混合研磨方法制备磁性腐殖酸(MHAS)复合材料,并将其作为磁固相萃取的吸附剂选择性分离和富集食用油脂中的苯并芘(BaP)。结合高效液相色谱-荧光检测法(HPLC-FLD),建立了食用油中BaP检测的新方法。该方法整个样品前处理过程在15min内即可完成,对目标物BaP的检测限低至0.04ng/g,在0.1~100ng/g范围内线性良好(R=0.999),日内(n=5)和日间(n=3)相对标准偏差分别小于3.5%和15.8%。将该方法应用于多种食用油中BaP的检测,每种食用油中均有不同含量的BaP被检出,对12种常见食用油的加标回收率在74.2%至120.6%之间,相对标准偏差小于11.0%。

Humic Acids-Based Magnetic Solid Phase Extraction for Analysis of Benzo[a]pyrene in Edible Oils by High-Performance Liquid Chromatography

In the present study,a rapid and simple method was developed and validated for the analysis of benzo[a]pyrene(BaP) in edible oils by combining magnetic humic acids(MHAs) solid phase extraction with high performance liquid chromatography with fluorescence detection(HPLC-FLD).The MHAs were fabricated via a simple co-mixing method based on an improved "aggregation-wrap" mechanism.Typically,the commercially available humic acids (Has) were directly mixed and ground with FeaO4 magnetic nanoparticles(MNPs) in a mortar,in which the MNPs were physically wrapped and adhered to tiny Has particles leading to the formation of MHAs.Due to the good adsorption ability of Has towards benzo[a]pyrene(BaP),the resultant MHAs were applied for the extraction of BaP from edible oils by the mode of magnetic solid phase extraction(MSPE).Several parameters affecting the extraction efficiency were investigated.Under the optimized conditions,the whole pretreatment process can be accomplished within 15 min by simple vortex.The linearity range of the proposed method was 0.1-100 ng/g with a correlation coefficient? of 0.999.The limit of quantification for the target BaP was 0.13 ng/g and an acceptable reproducibility was achieved by evaluating the intra-and inter-day precisions with relative standard deviations less than 3.5 ％ and 15.8％,respectively.Finally,the established MSPE-HPLC-FLD method was successfully applied to the analysis of BaP in several kinds of edible oils from local markets.