超高效液相色谱-串联质谱法测定香蕉中吡虫啉和高效氯氰菊酯

建立了香蕉中吡虫啉和高效氯氰菊酯多残留分析方法。样品经1%乙酸乙腈提取,N-丙基乙二胺(PSA)和石墨化炭黑(GCB)净化,以甲醇和2mmol/L乙酸铵水溶液为流动相,进行梯度洗脱分离,采用电喷雾正离子源模式(ESI+),多反应监测(MRM)采集数据,基质匹配外标法定量。吡虫啉和高效氯氰菊酯在0.001～0.1mg/L范围内线性关系良好,相关系数r> 0.9991,方法检出限(LOD)为1 pg,定量限(LOQ)为0.01 mg/kg。在0.01、0.05、0.10 mg/kg3个添加水平下,吡虫啉和高效氯氰菊酯在香蕉中的回收率为84.91%～104.78%,相对标准偏差(RSD)为1.23%～9.69%。该法操作简单、灵敏度高、重现性好,适用于香蕉中吡虫啉和高效氯氰菊酯的残留量测定。

Determination of Imidacloprid and β-cypermethrin in Banana by UPLC-MS/MS

A method was established for the simultaneous determination of imidacloprid and β-cypermethrin residues in bananas. The samples were extracted with 1% of acetic acid-acetonitrile, cleaned by PSA and GCB. Gradient elution separation was carried out with methanol and 2 mmol/L ammonium acetate solution as the mobile phase. The samples were determined using electrospray positive ionization (ESI ⁺) with multiple reaction monitoring (MRM) and then quantified by the matrix-matched external standard method. The results showed that the correlation coefficient r was > 0.9991, when the concentration ranged from 0.001 to 0.1 mg/L. The limit of detection (LOD) was 1 pg and the limit of quantification (LOQ) was 0.01 mg/kg. The recovery of imidacloprid and β-cypermethrin in banana was from 84.91% to 104.78% and the relative standard deviation (RSD) was from 1.23% to 9.69%. The method is simple, sensitive and reproducible for the determination of imidacloprid and β-cypermethrin residues in bananas.