We aimed to develop a rapid, simple and reproducible method based on LC–tandem mass spectrometry (LC–MS/MS) to analyze β‐agonist residues (clenbuterol, zilpaterol, ractopamine and isoxsuprine) in bovine tissues. The method was validated in accordance with the European Council Decision 2002/657/EC. The samples were homogenized, and then 10 mL of an acetate buffer was added to a 5‐g sample. The sample was then centrifuged at 12,000 rpm and filtered. Sodium hydroxide (2 m) was added to adjust pH of the sample that was centrifuged again. The extract was filtered through a solid‐phase extraction column. The residue was re‐dissolved in 250 μL acetonitrile and then subjected to LC–MS/MS. The separation was done on a C₁₈ column. The mobile phase consisted of 0.1% formic acid in deionized water and 0.1% formic acid in methanol. The mean recoveries of β‐agonists were in the range of 84.3%–119.1% with relative standard deviations (%RSDs) of 0.683%–4.05%. Decision limits and detection capabilities of the analytes ranged from 0.0960 to 4.9349 μg/kg and from 0.0983 to 5.0715, respectively. This method was used to detect four β‐agonists in 100 bovine muscle, 100 liver and 100 kidney tissues from a slaughterhouse. No residue was found above the maximum residue limit level.

中文翻译：

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液相色谱-串联质谱法测定牛组织中的β-激动剂残基。

我们旨在开发一种基于LC串联质谱（LC-MS / MS）的快速，简单且可重现的方法，以分析牛组织中的β-激动剂残留物（盐酸克伦特罗，齐帕特罗，雷克多巴胺和异苏定）。该方法已根据欧洲理事会第2002/657 / EC号决定进行了验证。将样品匀浆，然后将10 mL醋酸盐缓冲液添加到5 g样品中。然后将样品以12,000 rpm离心并过滤。加入氢氧化钠（2 m）以调节再次离心的样品的pH。萃取物通过固相萃取柱过滤。将残留物重新溶解在250μL乙腈中，然后进行LC-MS / MS分析。分离是在C _{18上完成的}柱。流动相由去离子水中的0.1％甲酸和甲醇中的0.1％甲酸组成。β-激动剂的平均回收率在84.3％–119.1％的范围内，相对标准偏差（％RSDs）为0.683％–4.05％。分析物的决策极限和检测能力分别为0.0960至4.9349μg/ kg和0.0983至5.0715。该方法用于检测屠宰场中100个牛肌肉，100个肝脏和100个肾脏组织中的4种β-激动剂。没有发现超过最大残留限量的残留物。