Chemical Department, University of Bialystok, 15-245 Bialystok, Poland.
J Agric Food Chem. 2023 Aug 2;71(30):11716-11725. doi: 10.1021/acs.jafc.3c03023. Epub 2023 Jul 24.
The occurrence of tigecycline (TGC), a new first glycylcycline antibiotic residues in food products harmfully influences potential human consumers health. Therefore, analysts are forced to develop new microextraction methods connected with modern extractants for effective isolation of this compound. For this purpose, deep eutectic solvents (DES) as the extraction media were used. Liquid-liquid microextraction (LLME) of tigecycline from milk samples with application of the hydrophobic deep eutectic solvents: decanoic acid:thymol (1:1), thymol:camphor (2:1), dodecanoic acid:menthol (2:1), and dodecanoic acid:dodecanol (1:1) was developed. The studied samples were subjected to a deproteinization process using trichloroacetic acid solution and acetonitrile. The optimal microextraction parameters, molar ratio of DES components, amount of extraction solvents, pH of milk sample, shaking, and centrifugation time, were chosen. Tigecycline in the obtained microextracts of deep eutectic solvents was analyzed using a liquid chromatographic technique connected with a tandem mass spectrometry (LC-MS/MS) system. The limits of detection and quantification values for TGC determination followed by DES-LLME-LC-MS/MS method were in the 1.8 × 10 mol L (0.01 μg kg) to 4.0 × 10 mol L (2.28 μg kg) and 5.5 × 10 mol L (0.03 μg kg) to 1.2 × 10 mol L (6.84 μg kg) ranges, respectively. The RSD values of precision were in the range 1.4-7.8% (intraday) and 5.4-11.7% (interday). The developed procedures were used for the determination of tigecycline in different bovine milk samples.
替加环素（TGC）的出现，一种新型的甘氨酰环素抗生素残留会对人类消费者的健康造成危害。因此，分析人员被迫开发新的微萃取方法，并结合现代萃取剂，以有效分离这种化合物。为此，使用了深共晶溶剂（DES）作为萃取介质。采用疏水性深共晶溶剂：癸酸：百里酚（1:1）、百里酚：樟脑（2:1）、十二酸：薄荷醇（2:1）和十二酸：十二醇（1:1）从牛奶样品中进行了替加环素的液-液微萃取（LLME）。研究的样品经过三氯乙酸溶液和乙腈的蛋白沉淀处理。选择了最佳的微萃取参数，即 DES 成分的摩尔比、萃取溶剂的用量、牛奶样品的 pH 值、搅拌和离心时间。采用液相色谱技术与串联质谱（LC-MS/MS）系统对所得深共晶溶剂微萃取物中的替加环素进行了分析。通过 DES-LLME-LC-MS/MS 方法测定 TGC 的检测限和定量限分别为 1.8×10 mol L（0.01μg kg）至 4.0×10 mol L（2.28μg kg）和 5.5×10 mol L（0.03μg kg）至 1.2×10 mol L（6.84μg kg）。精密度的 RSD 值在 1.4-7.8%（日内）和 5.4-11.7%（日间）范围内。所开发的程序用于不同牛奶奶样中替加环素的测定。
