复合式提取净化体系结合超高效液相色谱-串联质谱法检测畜禽肉中120种抗生素药物残留

建立了畜禽肉中兽药抗生素的复合式预处理方法,同时对8大类120种理化性质差异较大的目标化合物进行有效的提取和净化,并通过超高效液相色谱-串联质谱仪对其进行准确的筛查分析。样品经Na_2EDTA-Mcllvaine缓冲液溶解分散,由1.5%(v/v)甲酸乙腈提取,采用Oasis PRiME HLB通过式固相萃取、正己烷液液萃取两种方式先后对提取液进行净化。目标物在Atlantis~® T3色谱柱(100 mm×2.1 mm, 3μm)上,以乙腈和0.1%(v/v)甲酸水溶液为流动相进行梯度洗脱分离,在正离子(ESI^+)多反应监测(MRM)模式下进行定性定量分析。实验考察了不同pH条件的提取溶剂和不同净化方式对目标化合物回收率的影响并优化其条件。所建立的方法确保120种兽药在1.0～50.0μg/L范围内线性关系良好,线性相关系数(r^2)≥0.995 3,其中89种化合物的r^2≥0.999 0。7种化合物的定量限(LOQ)为10.0μg/kg, 21种化合物的LOQ为5.0μg/kg,其余92种化合物的LOQ均≤2.0μg/kg。低、中、高3个添加水平下的平均回收率为71.5%～109.2%,相对标准偏差为0.6%～15.3%。该方法灵敏高效,回收率优良,重复性稳定,适用于畜禽肉中多种抗生素药物的同时筛查检测。

Simultaneous determination of 120 veterinary antibiotics in meat by combined pretreatment system coupled with ultra-performance liquid chromatography-tandem mass spectrometry

A comprehensive pretreatment system was developed to simultaneously extract and purify 120 veterinary antibiotics, possessing various physicochemical properties in eight categories. This system was coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the detection of the antibiotics. The samples were dissolved and dispersed by a Na₂ EDTA-Mcllvaine buffer, extracted with acetonitrile containing 1.5% (v/v) formic acid, and cleaned using an Oasis PRiME HLB SPE system followed by n-hexane liquid purification. The separation of residue targets was performed on an Atlantis^® T3 column (100 mm×2.1 mm, 3 μm) with a gradient elution of 0.1% (v/v) formic acid aqueous solution and acetonitrile as mobile phases and detected by UPLC-MS/MS with the multiple reaction monitoring (MRM) mode via ESI⁺ ionization. The pH of the extraction solvent and the purification method were optimized to promote the target recoveries. All targets showed good linear ranges from 1.0 to 50.0 μg/L, while all their correlation coefficients (r²) were higher than 0.9953, including r² values of 89 targets being over 0.9990. The limits of quantification (LOQs) of seven targets were 10.0 μg/kg; 21 targets, 5.0 μg/kg; and the remaining 92 targets, not higher than 2.0 μg/kg. The average recoveries on three spiked levels (low, medium, and high) for all targets ranged from 71.5%-109.2%, with RSD ranging from 0.6%-15.3%. The combined system, exhibiting satisfying recovery and stable repeatability, can be suitably employed for the simultaneous determination of multiple veterinary antibiotics in animal-derived meat products.