UPLC-MS/MS测定小麦粉及其制品与小麦粉添加剂中新型非法添加物乙酰氧肟酸

Determination of the New Illegal Additive Acetohydroxamic Acid in Wheat Flour, Wheat-flour Products and Wheat-flour Additives using UPLC-MS/MS

摘要:

建立了超高效液相色谱-串联质谱法（UPLC-MS/MS）测定小麦粉及其制品与小麦粉添加剂中新型非法添加物乙酰氧肟酸的分析方法。方法选取小麦粉、小麦粉添加剂、面皮、面条、馒头等5种具有代表性的样品为研究基质，以甲醇为提取溶剂，经超声和涡旋振荡提取，高速离心、过滤，通过T3色谱柱（2.1 mm×150 mm，3 μm）分离，以0.10%（体积分数）甲酸溶液和甲醇作为洗脱流动相，采用大气压化学电离源、多反应监测模式检测，外标法定量。结果表明，乙酰氧肟酸的溶剂和基质标准曲线在0.075~5.00 mg/L范围内线性关系良好，相关系数均大于0.999，检出限为0.25 mg/kg，加标回收率为78.49%~108.61%，相对标准偏差（RSD，n=6）为1.67%~7.50%。该方法抗干扰能力强，准确度高，适用于小麦粉及其制品与小麦粉添加剂中乙酰氧肟酸的测定。

Abstract:

An analytical method based on ultra-performance liquid-chromatography-tandem mass spectrometry was developed for the determination of a new illegal additive, acetohydroxamic acid (AHA), in wheat flour, wheat-flour products, and wheat-flour additives. Five representative samples (wheat flour, a wheat-flour additive, dough, noodles, and steamed bun) were selected as the study matrices. AHA was first extracted using ultrasonic and vortex oscillation with methanol as the extraction solvent, subjected to high-speed centrifugation and filtration, and then separated using a T3 column (2.1 mm×150 mm, 3 μm) with a mixture of 0.10% (volume fraction) aqueous formic acid and methanol as the eluting mobile phase. Finally, it was quantified using an external standard method using an atmospheric pressure chemical ionization source (APCI) and multiple reaction monitoring mode. The results showed that the solvent and matrix standard curves of AHA had good linearity in the 0.075~5.00 mg/L range, with correlation coefficients>0.999. The limit of detection was 0.25 mg/kg, the spike recovery rate was 78.49%~108.61%, and the relative standard deviation (RSD, n=6) was 1.67%~7.50%. This method is suitable for the determination of AHA in wheat flour, wheat-flour products and wheat-flour additives, exhibiting good anti-interference capacity and high accuracy.