搅拌棒吸附萃取-高效液相色谱法测定红茶中15种多环芳烃

Determination of 15 polycyclic aromatic hydrocarbons in black tea by stirring bar sorptive extraction and high performance liquid chromatography

目的建立基于搅拌棒吸附萃取(SBSE)结合高效液相色谱-荧光检测(HPLC-FLD)测定红茶中15种多环芳烃的简便方法。方法研究甲醇和NaCl添加量、提取时间、解吸步骤以及基质效应对样品富集效率的影响,并在优化参数下将搅拌棒置于10 ml红茶样品中以750 r/min转速室温下提取120 min,萃取完成后以160μl乙腈-水解析后上机。结果在优化的实验条件下,15种多环芳烃在1 ng/L~1 200 ng/L浓度内呈良好线性关系,相关系数(r)> 0.998,检出限(S/N=3)为0.1 ng/L~8.7 ng/L,定量限为0.4 ng/L~27.5 ng/L,平均回收率在24.9%~88.7%。结论该方法简便、准确、环保、灵敏度高、选择性好,可满足红茶样品中多组分痕量多环芳烃的测定要求,为多环芳烃的残留分析提供了新的技术平台。

Objective A simple mathod based on stir bar sorptive extraction(SBSE) and high-performance liquid chromatography-fluorescence detection( HPLC-FLD) is presented for the determination of 15 polycyclic aromatic hydrocarbons(PAHs) in black tea.Methods SBSE conditions such as methanol and salt addition, extraction time, desorption steps and matrix effect, were examined. Under the optimized parameters, the stirring rod was placed in a 10 ml black tea sample and extracted at room temperature at 750 r/min for 120 min. After the extraction was completed, it was parsed with 160 μl of acetonitrile-water and then put on the machine.Results Under optimized experimental conditions, the 15 PAHs showed a good linear relationship within the concentration range of 1 ng/L-1 200 ng/L, the correlation coefficient(r) was greater than0. 998, the detection limit(S/N = 3) was 0. 1 ng/L-8. 7 ng/L, and the quantification limit was 0. 4 ng/L-27. 5 ng/L, and the average recovery rate is between 24. 9%-88. 7%.Conclusion The method is simple, accurate, environmentally friendly,sensitive and selective. It can meet the requirements for the determination of trace polycyclic aromatic hydrocarbons in black tea samples and provides a new technical platform for the analysis of polycyclic aromatic hydrocarbons.