气相色谱-三重四极杆串联质谱法同时测定焙烤食品中28种邻苯二甲酸酯

建立了气相色谱-三重四极杆串联质谱(GC-MS/MS)同时测定焙烤食品中28种邻苯二甲酸酯类(PAEs)物质残留量的方法。样品经乙酸乙酯超声提取,用中性氧化铝净化后进行检测。经程序升温气化进样口(PTV)不分流进样,TR-5MS色谱柱(30 m×0.25 mm×0.25 μ m)进行色谱分离,在选择反应监测(SRM)模式下进行质谱扫描,采用内标法定量。28种邻苯二甲酸酯的线性范围,除邻苯二甲酸二异壬酯(DINP)在0.1~20 mg/L外,其余27种均在0.05~10 mg/L范围内呈线性关系,相关系数r²≥0.9962。方法检出限范围为0.1~9.8 μ g/kg,方法定量限范围为0.4~32.6 μ g/kg。分别在面包、饼干、糕点、馅料4类样品中进行低、中、高3个添加水平的加标回收试验,加标回收率为81.0%~117%,相对标准偏差(RSD, n=6)为1.3%~13.6%。用建立的方法测定了不同焙烤食品中塑化剂的含量。该方法操作简单,可靠性高,适用范围广,适用于焙烤食品中邻苯二甲酸酯类物质残留量的检测。

Determination of 28 phthalate esters in baked foods by gas chromatography-triple quadrupole mass spectrometry

An efficient method using gas chromatography-triple quadrupole mass spectrometry for the determination of 28 phthalate ester residues in bakery foods was established. The samples were extracted with ethyl acetate, and cleaned up with neutral alumina. The separation was performed on a TR-5MS capillary column (30 m×0.25 mm×0.25 μ m) by programmed temperature vaporization (PTV) with splitless mode. Meanwhile the identification and quantification were performed by GC-MS/MS in selected reaction monitoring (SRM) mode and using the internal standard method. The calibration curves of the 27 phthalate esters showed good linearities in the range of 0.05-10 mg/L, except diisononyl ortho-phthalate (DINP) which was in the range of 0.1-20 mg/L, with the correlation coefficients not less 0.9962. The limits of detection (LODs) were 0.1-9.8 μ g/kg and the limits of quantification (LOQs) were 0.4-32.6 μ g/kg. With the proposed method, the spiked recoveries were evaluated in four types of baked foods (bread, biscuits, cakes, stuffing) at low, medium and high concentrations. The results showed that the average recoveries of the 28 PAEs were in the range of 81.0%-117%, and the relative standard deviations (RSDs, n=6) were in the range of 1.3%-13.6%. The method was successfully applied in the investigation of the PAEs distribution in baked foods. The method is suitable for the determination of the 28 PAEs in baked foods with easy operation, high accuracy and precision.