气相色谱-质谱联用法测定食品中丙烯酰胺

DETERMINATION OF ACRYLAMIDE IN FOOD BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY

[目的]研究检测食品中致癌物丙烯酰胺的气相色谱-质谱联用测定方法,用于各种食品中丙烯酰胺的测定。[方法]食品样用正己烷除去油脂后,用水提取其中的丙烯酰胺,采用Carrez试剂对样品液进行净化,以甲基丙烯酰胺作为内标物,溴化衍生后,用气相色谱分离后以质谱测定其含量。色谱条件:色谱柱为HP-5MS弹性石英毛细管色谱柱,30m×0.25mm×0.25μm;载气为高纯氦气,流速1ml/min;进样口温度:250℃;进样方式:无分流进样;柱温:初温80℃,保持8min,以15℃/min升温至250℃,保持3min;质谱条件:离子源为EI源,电子能量70eV;检测方式为选择性离子监测方式,传输线温度250℃;离子源温度230℃;四极杆温度150℃;检测电压1.40kV;溶剂延迟时间6min。丙烯酰胺衍生物选择离子m/z150定量,甲基丙烯酰胺衍生物以m/z164定量。外标法定量。[结果]丙烯酰胺在5～500μg/L浓度范围内线性良好,相关系数r=0.99981;方法定性检出限为1.6μg/kg,定量检出限5μg/kg,回收率大于96%,相对标准偏差(RSD)小于6.7%。[结论]建立的方法测定食品中丙烯酰胺满足痕量分析要求,并具有操作简单、干扰少、快速、准确可靠等特点,可用于我国食品中丙烯酰胺状况调查。

[ Objective] To study a method for the detemination of acrylamide in food by gas chromatographymass spectrometric method （GC/MS） ： [ Methods] Homogenized food samples were first defatted by liquid-hquid partition, and extracted with distilled water then the solutions were cleaned by Canez solution and centrifuged. With the aid of methyl-acry- lamide internal standard, the acrylamide in foods was determined by GC-MS after derived by neoformative bromine. The GC system consisted of HP-5MS column （30 m × 0.25 mm× 0125 μm） , carrier of helium （ 1 ml/min） , injection vohnne 1μl with splitless, column temperature program： initial column temperature 80℃, keeping 8 minutes and rising to 250% with rate of 15% per minute, keeping 3 minutes. The MS system consists of electron ionization （EI） and detected by selective ion moni- toring （SIM） . [ Resultsl The linear ranges of concentration of acrylamide was 5-500 μg/L （r = 0.999 81） . The detection limit of the method was 1.6 μg/kg （S/N=3）, and the limit of quantification was 5 μg/kg （S/N=10） . The recoveries was over 96%, and the relative standard derivations were lower than 6.7%. [Conclusion] The method of determination of acrylamide in foods by GC/MS is with less disturbance, easy to operate and accurate. It can be used in the analysis of the acrylamide in foods.