该研究建立了水果中吗啉脂肪酸盐果蜡的气相色谱-三重四极杆质谱（gas chromatography-tandem mass spectrometry，GC-MS/MS）分析方法。样品使用改进QuEChERS（quick，easy，cheap，effective，rugged and safe）方法，经1%甲酸-乙腈提取，乙二胺-N-丙基甲硅烷（PSA）和石墨化炭黑吸附剂（GCB）净化，使用5.5 mol/L盐酸和4.3 mol/L亚硝酸钠在冰浴条件下衍生3 h，以HP-FFAP毛细管柱进行分离，在电子轰击源（EI）和多反应监测模式下进行测定，基质曲线外标法定量。结果表明，吗啉脂肪酸盐通过亚硝基化反应可衍生成稳定的亚硝基吗啉（N-nitrosomorpholine，NMOR），目标衍生化合物峰形较好，在1~800 µg/L范围内线性良好，相关系数大于0.99，检出限为0.14~1.09 µg/kg，定量限为0.47~3.63 µg/kg，加标回收率范围为73.6%~118.5%，相对标准偏差（RSD）为3.6%~15.2%（n=6）。该方法准确、高效，在实际样本中检出率较高，适用于水果中吗啉脂肪酸盐果蜡的定性和定量检测。

In this study, a gas chromatography-tandem mass (GC-MS/MS) method was developed to determine the morpholine fatty acid salt in fruits. Samples were analyzed using a modified QuEChERS (quick, easy, cheap, effective, rugged and safe) method, through being extracted with 1% formic acid-acetonitrile, purified with ethylenediamine-N-propylsilane (PSA) and graphitized carbon black adsorbent (GCB), derivatized with 5.5 mol/L HCl and 4.3 mol/L NaNO2 in ice bath for 3 h, separated by HP-FFAP capillary column, and measured in electron bombardment ion source (EI) and multiple reaction monitoring mode. Matrix calibration curve and external standard method were used for quantification. The results showed that morpholine fatty acid salts can be derivatized into stable nitrosomorpholine (NMOR) through nitrosation. The peak shape of the target derivative compound was good, The linearity in the analyte range of 1~800 µg/L was good, with the correlation coefficient higher than 0.99, the limit of detection as 0.14~1.09 µg/kg, the limit of quantitation as 0.47~3.63 µg/kg, the recovery rate of spiked standard as 73.6%~118.5%, and the relative standard deviation (RSD) as 3.6%~15.2% (n=6). This method is accurate and efficient, has a high detection rate in actual samples, and is suitable for qualitative and quantitative detection of morpholine fatty acid salt in fruits.

国家重点研发计划重点专项（2018YFC1602303）；湖北省自然科学基金青年项目（2019CFB380）