In this study, a new floating dispersive solid phase extraction method based on deep eutectic solvents has been developed in a home-made extraction device for the extraction of four tetracycline antibiotics from milk samples. In this approach, the sorbent (activated carbon) was dispersed in whole parts of solution with the aid of air stream and floated on top of the solution with the aid of the surfactant (lauryl betaine) and air bubbles. After collection of the sorbent, the adsorbed analytes were eluted with tetrabutyl ammonium chloride–propionic acid deep eutectic solvent under sonication. In this method, there was no need of organic dispersive and extraction solvents and the used sorbent was collected on top of the solution and collected without centrifugation. The validation parameters showed that low limits of detection (0.1-0.3 μg/kg) and quantification (0.6-1.0 μg/kg), acceptable enrichment factors (52-60), efficient extraction recoveries (80-91%), and satisfactory relative standard deviations (≤9.8%) were obtained. Eventually, the method was successfully applied on different milk samples and tetracycline was determined in them.

中文翻译：

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开发表面活性剂辅助分散固相萃取，使用深共熔溶剂萃取牛奶样品中的四种四环素抗生素残留

本研究在自制萃取装置中开发了一种基于低共熔溶剂的浮动分散固相萃取新方法，用于从牛奶样品中萃取四种四环素类抗生素。在这种方法中，吸附剂（活性炭）在气流的帮助下分散在整个溶液中，并在表面活性剂（月桂基甜菜碱）和气泡的帮助下漂浮在溶液的顶部。吸附剂收集后，吸附的分析物在超声处理下用四丁基氯化铵-丙酸低共熔溶剂洗脱。在这种方法中，不需要有机分散剂和萃取溶剂，用过的吸附剂收集在溶液的顶部，无需离心即可收集。验证参数显示低检测限 (0.1-0. 3 μg/kg) 和定量 (0.6-1.0 μg/kg)、可接受的富集因子 (52-60)、有效提取回收率 (80-91%) 和令人满意的相对标准偏差 (≤9.8%)。最终，该方法成功应用于不同的牛奶样品，并测定了其中的四环素。