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β-受體激動劑俗稱“瘦肉精"，屬于苯乙醇胺類藥物，醫(yī)學(xué)臨床上主要用于擴(kuò)張支氣管和增加肺通氣量，可治療支氣管哮喘等呼吸系統(tǒng)疾病。目前針對動物組織、尿液、血液中 β-受體激動劑的檢測主要采用酶解結(jié)合固相萃取方法，但酶解時(shí)間通常達(dá)16小時(shí)以上，并且固相萃取時(shí)間也較長，特別是對實(shí)際市場監(jiān)管常需要批量檢測大量的實(shí)際樣品，工作效率較低，純手動操作帶來的檢測偏差也較大。

為解決這一問題，中國農(nóng)業(yè)科學(xué)院農(nóng)業(yè)質(zhì)量標(biāo)準(zhǔn)與檢測技術(shù)研究所、北京市畜牧總站、上海市獸藥飼料檢測所、北京市飼料監(jiān)察所有關(guān)研究人員提出《全自動固相萃取結(jié)合超聲探針輔助酶解快速批量定量測定動物源性食品中的22種β-受體激動劑殘留》，并將有關(guān)研究成果發(fā)布在《Food Chemistry》 期刊。本研究采用超聲探針輔助酶解，從動物源性食品中充分提取β-激動劑僅需2分鐘，結(jié)合全自動固相萃取的批量、自動化處理，30分鐘內(nèi)可同時(shí)處理 36 份樣品。

“A high demand exists in veterinary drug residual analysis for rapid, automatic and high-throughput analytical techniques that produce data simultaneous and faster. Here, we describe a combined automated solid-phase extraction (SPE) and enzymatic probe sonication (EPS), subsequently ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the quick extraction, automated clean-up as well as simultaneous quantification of 22 β-agonists residues in animal-derived foods. Enhanced by the ultrasonic probe, only 2 min was needed for exhaustively extraction of β-agonists from foods of animal-origin; whereas traditional enzymatic digestion methods require hours or even days, which making it more appropriate for high throughput biomonitoring.Moreover, the clean-up and pre-concentration procedures were conducted on the automatic SPE, which allowed 36 samples being performed simultaneously within 30 min. The method was successfully applied for analyzing 56 animal-derived food samples, 53.6 % of which contained detectable levels of at least one kind of β-agonists. Interestingly, both the detection rate and residual level of β-agonists in the ruminants (bovine and sheep) were higher as compared with the swine. Concerning the real food samples analyzed, the findings of this study suggest that stricter measures should be adopted to control the illegal usage of β-agonists on the farm animals, particularly for the ruminants."