Department of Analytical Chemistry, Certification and Quality Management, National Research Technological University, 68 Karl Marx Street, Kazan, 420015, Russia; Department of Analytical Chemistry, Institute of Chemistry, Saint-Petersburg University St. Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg, 199034, Russia.
Department of Analytical Chemistry, Institute of Chemistry, Saint-Petersburg University St. Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg, 199034, Russia.
Talanta. 2024 Nov 1;279:126666. doi: 10.1016/j.talanta.2024.126666. Epub 2024 Aug 3.
In this work, coacervation in primary amines solutions with hydrophobic natural deep eutectic solvents based on terpenoids and carboxylic acids was demonstrated for the first time. A liquid-phase microextraction approach was developed based on supramolecular solvent formation with primary amine acting as amphiphile and hydrophobic deep eutectic solvent making up mixed vesicles and serving as coacervation agent. Such supramolecular solvents could be used to separate wide range of substances from different aqueous media, such as food products, biological liquids and wastewaters. It is important that both hydrophobic and ionic interactions with supramolecular aggregates take place ensuring synergetic effect and better extraction ability, which is significant in separating relatively polar analytes. Different primary amines and deep eutectic solvents were investigated for liquid-phase microextraction of proof-of-concept amphoteric analyte (enrofloxacin, widely used veterinary fluoroquinolone antibiotic) and its determination by high-performance liquid chromatography with fluorescence detection using Shimadzu LC-20 Prominence chromatograph and RF-20A fluorescence detector. It was found that the supramolecular solvent based on 1-nonylamine, formed after addition of a deep eutectic solvent based on menthol and hexanoic acid (molar ratio of 1:1), provided maximum extraction recovery (85 %) and maximum enrichment factor (34). To characterize the extraction system, the composition of the phases was investigated, and cryo-transmission electron microscopy images were obtained. Vesicular aggregates were observed in the supramolecular solvent. The extraction mechanism was proposed in terms of formation of mixed aggregates to capture the analyte. Limit of detection was found to be 7 μg kg, while linear range of 20-250 μg kg was established. Relative standard deviation values were lower than 7 %. Relative bias did not exceed 12 %.
在这项工作中，首次展示了基于萜类和羧酸的疏水性天然深共晶溶剂中伯胺溶液的凝聚作用。基于伯胺作为两亲性物质和疏水性深共晶溶剂形成混合囊泡并作为凝聚剂的超分子溶剂形成，开发了一种液相微萃取方法。这种超分子溶剂可用于从不同的水介质中分离广泛的物质，如食品、生物液体和废水。重要的是，超分子聚集体的疏水和离子相互作用确保了协同效应和更好的萃取能力，这对于分离相对极性的分析物非常重要。研究了不同的伯胺和深共晶溶剂，用于液相微萃取两性分析物（恩诺沙星，广泛使用的兽医氟喹诺酮抗生素）及其通过高效液相色谱法与荧光检测的测定，使用岛津 LC-20 卓越色谱仪和 RF-20A 荧光检测器。结果发现，在添加基于薄荷醇和己酸的深共晶溶剂（摩尔比为 1:1）后形成的 1-壬胺基超分子溶剂提供了最大的萃取回收率（85%）和最大的富集因子（34）。为了表征萃取体系，研究了各相的组成，并获得了低温传输电子显微镜图像。在超分子溶剂中观察到囊泡状聚集体。根据形成混合聚集体来捕获分析物的原理，提出了萃取机制。检测限为 7μgkg，线性范围为 20-250μgkg。相对标准偏差值低于 7%。相对偏差不超过 12%。
