TY - JOUR

T1 - Microextraction of sulfonamides from milk samples based on hydrophobic deep eutectic solvent formation by pH adjusting

AU - Pochivalov, Aleksei

AU - Cherkashina, Ksenia

AU - Shishov, Andrey

AU - Bulatov, Andrey

N1 - Publisher Copyright: © 2021 Elsevier B.V.

PY - 2021/10/1

Y1 - 2021/10/1

N2 - A novel approach for liquid-liquid microextraction via formation of hydrophobic deep eutectic solvent by pH adjusting was suggested. This study demonstrated for the first time that an alkaline aqueous solution of terpenoid and medium-chain saturated fatty acid can serve as a source of precursors for deep eutectic solvent (DES) formation by extraction system acidification. In this case, the microdroplets of in situ formed DES phase appear in the whole volume of the homogeneous solution, simultaneously extracting the analytes. The proposed approach enables one to avoid heating and usage of auxiliary energy sources, which considerably simplifies the procedure and minimizes the extraction time in comparison with the existing analogues. The proposed approach was successfully applied to the determination of sulfamethazine, sulfamethoxazole, sulfaquinoxaline and sulfadiazine in milk samples. The nature of precursors played an important role in the extraction process, providing different types of interaction with the analytes. The preconcentration factors ranged from 22 to 103, rising with an increase of hydrophobicity of the analyte. In situ formation of fine droplets of the solvent provided fast mass-transfer of sulfonamides (30 s). The limits of detection calculated from the calibration plot based on 3σ were equal to 1 μg L−1 for sulfamethazine and sulfaquinoxaline, 3 μg L−1 for sulfamethoxazole, and 5 μg L−1 for sulfadiazine.

AB - A novel approach for liquid-liquid microextraction via formation of hydrophobic deep eutectic solvent by pH adjusting was suggested. This study demonstrated for the first time that an alkaline aqueous solution of terpenoid and medium-chain saturated fatty acid can serve as a source of precursors for deep eutectic solvent (DES) formation by extraction system acidification. In this case, the microdroplets of in situ formed DES phase appear in the whole volume of the homogeneous solution, simultaneously extracting the analytes. The proposed approach enables one to avoid heating and usage of auxiliary energy sources, which considerably simplifies the procedure and minimizes the extraction time in comparison with the existing analogues. The proposed approach was successfully applied to the determination of sulfamethazine, sulfamethoxazole, sulfaquinoxaline and sulfadiazine in milk samples. The nature of precursors played an important role in the extraction process, providing different types of interaction with the analytes. The preconcentration factors ranged from 22 to 103, rising with an increase of hydrophobicity of the analyte. In situ formation of fine droplets of the solvent provided fast mass-transfer of sulfonamides (30 s). The limits of detection calculated from the calibration plot based on 3σ were equal to 1 μg L−1 for sulfamethazine and sulfaquinoxaline, 3 μg L−1 for sulfamethoxazole, and 5 μg L−1 for sulfadiazine.

KW - Hydrophobic deep eutectic solvent

KW - Liquid chromatography

KW - Microextraction

KW - Milk

KW - Sulfonamides

KW - SOLID-PHASE EXTRACTION

UR - http://www.scopus.com/inward/record.url?scp=85110523540&partnerID=8YFLogxK

U2 - 10.1016/j.molliq.2021.116827

DO - 10.1016/j.molliq.2021.116827

M3 - Article

AN - SCOPUS:85110523540

VL - 339

JO - Journal of Molecular Liquids

JF - Journal of Molecular Liquids

SN - 0167-7322

M1 - 116827

ER -