QuEChERS结合GC-MS法快速检测酿酒玉米中14种邻苯二甲酸酯类塑化剂

建立了QuEChERS结合气相色谱-质谱法(GC-MS)快速检测玉米中14 种邻苯二甲酸酯类塑化剂(PAEs)的方法。样品经乙腈溶液提取,无水硫酸镁和氯化钠盐析后,经N-丙基乙二胺(PSA)填料、十八烷基键合硅胶(C₁₈)及石墨炭黑(GCB)净化,采用选择离子模式,外标法定量。结果表明:14 种PAEs在1~500 μg/L范围内,采用基质匹配法绘制标准曲线,线性良好,相关系数在0.9945~0.9995之间;在15、150、500 μg/kg的加标水平下,平均回收率为80.0%~109.8%,相对标准偏差均小于9.0%;检出限(S/N=3)与定量限(S/N=10)分别为0.1~2.5和0.13~5.0 μg/kg。将该方法应用于6 个不同产地的玉米原料检测,结果显示:样品中检出邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、邻苯二甲酸二异丁酯、邻苯二甲酸二丁酯和邻苯二甲酸二(2-乙基)己酯此5种塑化剂,且塑化剂含量均低于国标限量标准。该方法高效、快速、灵敏度高,适合于玉米样品的日常监测。

Rapid determination of 14 phthalate esters in corn by QuEChERS-based gas chromatography/mass spectrometry method

A modified QuEChERS method was developed for the simultaneous determinationn of 14 phthalate esters(PAEs)in corn prior to gas chromatography-mass spectrometry(GC-MS)analysis. All of the PAEs in corn samples were extracted into acetonitrile and salted out by anhydrous MgSO₄ and NaCl. Then,the PAEs in the supernatant after clean-up by primary secondary amine(PSA),octadecyl silica(C₁₈),and graphitized carbon black(GCB)were subjected to GC-MS analysis. External standard quantification was used to determine the extraction efficiency of each sample. As a result,14 PAEs possessed an excellent linear relation by using matrix-matched curve under 1~500 μg/L,and the correlation coefficients were 0.9945~0.9995.The recoveries of 14 PAEs in corn matrixes at three spiked levels of 15,150 and 500μg/kg ranged from 80.0% to 109.8% with relative standard deviations below 9.0%. The LODs and LOQs for PAEs,based on S/N of 3 and 10,ranged from 0.1 to 2.5 μg/kg and 0.13 to 5.0 μg/kg,respectively. The applicability of the method was properly validated using six corns,and the results revealed that the dimethyl phthalate(DMP),diethyl phthalate(DEP),diisobutyl phthalate(DIBP),dibutyl phthalate(DBP),and bis(2-methoxyethyl)phthalate(DEHP)were detected in all the samples. The content of PAEs is lower than the standard of GB. Overall,the developed QuEChERS-GC/MS method could be considered as a promising method for routine monitoring of PAEs residue in corn since the procedure was easy,fast,and effective.