基于超高效液相色谱串联质谱法的番茄果实和土壤中氟吡菌胺残留测定

建立了番茄果实和土壤中氟吡菌胺残留的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。用乙腈水溶液提取样品中的氟毗菌胺,以C_(18)柱为分析柱、乙腈-甲酸水溶液为流动相,采用超高效液相色谱-串联质谱多反应监测、电喷雾正离子源、外标法定量。氟吡菌胺在0.05~1.00 mg/L范围内与峰面积呈良好的线性关系,线性方程为y=6964.10x-143.28,决定系数为0.996 8。向对照番茄果实、对照土壤中分别添加氟吡菌胺标样,使其添加量分别为0.10 mg/kg、0.40 mg/kg和2.00 mg/kg,平均回收率分别为92.43%~103.32%和92.75%~104.46%,相对标准偏差分别为3.8%~4.9%和3.4%~4.4%。番茄果实和土壤中氟吡菌胺的定量限分别为1.0μg/kg和1.7μg/kg,检出限分别为0.3μg/kg和0.5μg/kg。

Determination of the fluopicolide residue in the tomato fruit and the soil via UPLC-MS/MS

The given article is to devote itself to the identification and determination of fluopieolide residues in the tomato fruit and the soil in which the tomato grows up.For the said purpose,we have developed and proposed a rapid and convenient ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to determine those residues.By using the method,we have extracted the soil and the homogenized tomato fruit samples in the mixed solvent of acetonitrile (+ 0.2％ formic acid,v/v) and water (2:1,v/v) in a centrifuge tube.The tube is required to be shaken for 30 min in a mechanical horizontal shaker.After 5 g of NaCl was added,the tube is supposed to be shaken for another 10 min in the shaker.And,next,the tube has to be centrifuged at 3 000 r/min for 2 min,with about 1 mL acetonitrile layer being filtered through a 0.22 μm filter and 10 μL of the filtrate being injected into the LC.A Waters ACQUITY UPLC instrument was used for analysis.And,in turn,it would be possible to realize the separation on an ACQUITY BEH C1s column (2.1 mm× 50 mm,1.7 μm) well-kept at the temperature of 35 ℃.The mobile phase has been found consisting of acetonitrile (eluent A) and water with 0.1％ (v/v) formic acid (eluent B),whereas the gradient elution can be conducted at a flowing rate of 0.300 mL/min according to the research program.The detection can be achieved with a Waters TQ triple-quadrupole mass spectrometer in positive electro-spray ionization (ESI +) and multiple reaction monitoring (MRM) modes.In so doing,it would be possible to find the excellent linear relationship between the fluopicolide concentration (x) in the range of 0.05-1.00 mg/L and the peak area (y),with the correlation coefficient (R2) being discovered as 0.996 8.And,now,it can be disclosed that at the three fortification levels,known as 0.10 mg/kg,0.40 mg/kg and 2.00 mg/kg,the average recovery rates of fluopicolide can be found ranging from 92.43％ to 103.32％ in the tomato fruit and 92.75％ to 104.46％ in the soil,with RSD varying in a range from 3.8％ to 4.9％ and 3.4 to 4.4％,respectively.The limit of quantification (LOQ) of the tomato fruit and the soil has been discovered to be 1.0 μg/kg and 1.7 μg/kg,respectively.And,the limit of detection (LOD) for them has been taken as 0.3 μg/kg and 0.5 μg/kg,correspondingly.Thus,it can be concluded that the method we have developed and proposed has been successfully validated by the identification and determination of fluopicolide residues in the field-treated tomato fruit and the soil samples.