超高效液相色谱-电喷雾串联质谱法同时测定土壤中四环素类抗生素及其降解产物

研究建立了超高效液相色谱电喷雾串联质谱法(UPLC/MS/MS)测定土壤中四环素(TC)、土霉素(OTC)、金霉素(CTC)、多西环素(DC)4种四环素类抗生素(TCs)及5种降解产物的残留分析方法。采用乙腈与EDTA-Mcllvaine缓冲液混合提取土壤样品中TCs，净化采用HLB固相萃取小柱，电离方式为ESI(+)，定量方法为多反应监测(MRM)模式。在0.001~0.5 mg/kg范围内, 4种四环素类抗生素及其降解产物的峰面积与质量浓度的线性关系良好( R2>0.99)。仪器检出限为1.085~15.780 μg/kg，方法的定量限为3.617~42.526 μg/kg。在3个添加水平 0.05、0.1和 0.5 mg/kg下，除脱水四环素和差向脱水四环素(其回收率<30%)外，其余四环素类抗生素及代谢产物在土壤中的添加回收率为62.1%~87.6%，相对标准偏差为2.35%~13.42%。该方法线性关系良好，灵敏度高，适用于土壤中四环素类抗生素及其降解产物的残留分析。

Determination of tetracyclines and their degradation products in soil using ultra-performance liquid chromatography-tandem mass spectrometry.

We developed a method for simultaneous determination of tetracycline (TC), oxytetracycline (OTC), chlortetracycline (CTC), doxycycline (DC) and their metabolites in soil by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) detection. The antibiotics were extracted using mixed solvent of acetonitrile and EDTA-Mcllvaine buffer solution and separated and purified by HLB solid phase extraction column. The purified antibiotics were detected by UPLC-MS/MS with ES(+) ionization and quantified in the multiple reaction monitoring (MRM) mode. Within 0.0010.5 mg·kg-1 range, we found a good linear relationship (R2>0.99) between the peak areas and concentrations of TCs and their metabolites, with limits of detection (LOD) and limits of quantification (LOQ) reaching 1.08515.780 and 3.61742.526 μg·kg-1, respectively. At the three addition levels of 0.05, 0.1 and 0.5 mg·kg-1, the average recovery rates for TCs and their metabolites in soil were 62.1%87.6%, with relative standard deviation (RSD) of 2.35%13.42%, except for ATC and EATC (<30%). This method is effective and meets the sensitivity, accuracy and precision demands for detecting residues of TCs and their metabolites in soil.