多重吸附同步净化-气相色谱-质谱法测定干性样品中丁烯氟虫腈的残留量

Determination of butene-fipronil residue in dry samples by multiple adsorption synchronous purification-gas chromatography-mass spectrometry

建立了干性样品中丁烯氟虫腈残留量的多重吸附同步净化(MASP)-气相色谱-质谱检测方法。前处理以1%乙酸-乙腈提取样品,应用MASP法对样品同时进行提取、盐析和净化,并利用气相色谱-质谱仪在选择离子扫描(SIM)模式下进行检测,以基质匹配标准溶液外标法定量。结果表明:丁烯氟虫腈在2～100μg/L范围内线性关系良好,相关系数(r2)不小于0.999;在2～10μg/kg添加水平范围内,丁烯氟虫腈的平均回收率为92.2%～97.5%,相对标准偏差(RSD,n=6)为2.69%～5.21%;方法检出限(S/N=3)为2μg/kg;定量限(S/N=10)为6μg/kg。本方法操作简便、快速、准确,可用于干性样品中丁烯氟虫腈的日常检测。同时,对丁烯氟虫腈的裂解机理进行了探讨。

A method was developed for the determination of butene-fipronil residue in dry sam- ples by multiple adsorption synchronous purification （MASP）-gas chromatography （GC）-mass spectrometry （MS）. After extracted with 1% acetic acid-acetonitrile, the samples were pre- treated with MASP method including extraction, salting-out and purification procedures, and analyzed with GC-MS under the selected ion monitoring （SIM） mode, and then quantified by matrix-match standard solution with external standard method. The results showed good linear- ity in the range of 2 - 100 μg/L with the correlation coefficients （ r2 ） not less than 0. 999. The average fortified recovery of butene-fipronil in samples was found in the range of 92.2% - 97.5% at three fortified levels from 2 to 10μg/kg, with the relative standard deviations of 2.69% - 5.21% （ n = 6）. The limit of detection （S/N = 3 ） for butane-fipronil was 2 μg/kg and the limit of quantification （S/N = 10） was 6 μg/kg. The method is simple, rapid and accurate, and could be used for the routine analysis of butane-fipronil in dry samples. Meanwhile, the pyrolysis mechanism of butane-fipronil, as a new substance, is discussed.