液相色谱-串联质谱法检测杨梅中农药残留基质效应研究

Study on matrix effects of pesticide residue detection in Myrica rubra by liquid chromatography-tandem mass spectrometry

中文关键词:  杨梅  液相色谱-串联质谱法  农药残留  基质效应

英文关键词:Myrica rubra  liquid chromatography-tandem mass spectrometry  pesticide residues  matrix effects

中文摘要:

      目的 研究杨梅中农药残留基质效应的影响因素和优化策略。方法 通过液相色谱-串联质谱法分别在不同的前处理方法、不同的农药和基质浓度(低、中、高浓度)、添加保护剂及改变液相色谱流速条件下, 对杨梅中农药残留进行检测, 分析其对基质效应的影响程度。运用方差分析比较不同检测条件的基质效应差异, 检验水准0.05。结果 在国家标准方法的基础上分别添加石墨化碳黑吸附剂、替换盐析剂、酸化乙腈等优化前处理条件能有效降低或消除基质效应; 不同农药质量浓度的基质效应存在差异, 中质量浓度(50 μg/L、100 μg/L)相较于低质量浓度(5 μg/L、10 μg/L)和高质量浓度(150 μg/L、200 μg/L)表现出较弱的基质效应; 不同基质稀释倍数的基质效应存在差异, 高稀释倍数(稀释×100)无基质效应, 中稀释倍数(稀释×50、×10、×5、×2)表现为弱基质效应, 未稀释的原液表现为强基质效应; 添加分析保护剂较标准方法能明显消除基质效应; 不同液相色谱流速的基质效应存在差异, 流速0.1 mL/min相较于0.3 mL/min和0.2 mL/min表现出强基质效应。结论 采用液相色谱-串联质谱法检测杨梅等复杂基质中农药残留时, 通过优化前处理方法、选择适宜基质稀释倍数与农药检测浓度、添加分析保护剂及设定适配流速, 可有效降低或消除基质效应。

英文摘要:

      Objective To investigate the influencing factors and optimization strategies for the matrix effects in pesticide residue analysis in Myrica rubra. Methods Pesticide residues in Myrica rubra were detected using liquid chromatography-tandem mass spectrometry under different conditions: Various sample pretreatment methods, different pesticide and matrix concentrations (low, medium, high), the addition of analyte protectants and varying liquid chromatography flow rates. The impact of these conditions on the matrix effect was analyzed. Analysis of variance (ANOVA) was used to compare the differences in matrix effects under different detection conditions, with a significance level of α=0.05. Results Optimizing the pretreatment conditions based on the national standard method—specifically by adding graphitized carbon black adsorbent, replacing the salting-out agent and using acidified acetonitrile—effectively reduced or eliminated the matrix effects. The matrix effects varied with pesticide concentration, showed a weaker effect at medium concentrations (50 μg/L, 100 μg/L) compared to low (5 μg/L, 10 μg/L) and high concentrations (150 μg/L, 200 μg/L). Different matrix dilution factors also resulted in varying matrix effects: High dilution (×100) showed no matrix effect, medium dilutions (×50, ×10, ×5, ×2) exhibited a weak matrix effects, and the undiluted sample extract showed a strong matrix effects. The addition of analyte protectants significantly eliminated the matrix effects compared to the standard method. The matrix effects also differed with liquid chromatography flow rates, with a flow rate of 0.1 mL/min demonstrating a stronger matrix effect compared to 0.3 mL/min and 0.2 mL/min. Conclusion When detecting pesticide residues in complex matrices like Myrica rubra using liquid chromatography-tandem mass spectrometry, the matrix effect can be effectively reduced or eliminated by optimizing the sample pretreatment method, selecting appropriate matrix dilution factors and pesticide concentrations, adding analyte protectants and setting compatible flow rates.