共价有机框架材料磁性固相萃取结合高效液相色谱-串联质谱法检测茶叶中黄曲霉毒素

Determination of Aflatoxins in Tea by Magnetic Solid Phase Extraction Based on Covalent Organic FrameworkCoupled with High Performance Liquid Chromatography-Tandem Mass Spectrometry

建立了一种基于共价有机框架材料的磁性固相萃取(magnetic solid phase extraction,M-SPE)结合高效液相色谱-串联质谱(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)方法,用于茶叶中4种黄曲霉毒素(aflatoxins,AFs)的高效测定。样品经过乙腈、水和冰醋酸按8.0∶1.9∶0.1(V/V)提取、离心、M-SPE和过滤,净化后滤液经正离子模式测定,并用HPLC-MS/MS法进行定量。建立的4种AFs分析方法在0.05~50μg/L范围内线性良好,决定系数R2>0.9992,加标回收率在67.6%~103.7%之间,日内、日间精密度均小于9.24%,方法检出限为0.01~0.06μg/kg,定量限为0.05~0.20μg/kg。本研究制备的共价有机框架材料对AFs吸附能力强,开发的M-SPE-HPLC-MS/MS适用于茶叶中AFs的快速、高灵敏、准确检测。

A magnetic solid phase extraction(M-SPE)based on covalent organic framework materials coupled with high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was developed for the efficient determination of four aflatoxins(AFs)in tea.The samples were extracted with a mixture of acetonitrile,water and glacial acetic acid(8.0:1.9:0.1,V/V)and centrifuged.The supernatant was evaporated to almost dryness,re-dissolved in water and pH adjusted,extracted M-SPE and filtered,and the filtrate was detected in the positive ion mode.The calibration curves for all analytes were linear in the range of 0.05–50μg/L with coefficients of determination(R2)>0.9992,the spiked recoveries were in the range of 67.6%-103.7%,and the relative standard deviations(RSDs)for intra-and inter-day precisions were less than 9.24%,the limits of detection(LODs)were in the range of 0.01-0.06μg/kg,and the limits of quantification(LOQs)of the developed method were in the range of 0.05-0.20μg/kg.The covalent organic framework material prepared in this study has a strong adsorption capacity for AFs,and M-SPE-HPLC-MS/MS is suitable for the rapid,highly sensitive and accurate detection of AFs in tea.