Salt‐assisted liquid–liquid extraction in microchannel

Abstract

In this study, for the first time, salt-assisted liquid-liquid extraction was performed in a microchannel system. The proposed design is based on the increase of contact surface area between target analytes and extracting phase during the sample and extracting phase transfer in microchannel. In this method, first sample solution, extracting solvent, and salt were mixed by stirrer and simultaneously delivered into a microchannel using a syringe pump. In order to optimize the influential parameters on the extraction efficiency of the proposed method, zidovudine and tenofovir disoproxil fumarate were selected as model analytes. The main parameters such as extracting solvent and its volume, salt amount, pH of sample solution, and microchannel shape, length, and its inner diameter were investigated and optimized. Under the optimized conditions, the proposed method was linear in the range of 0.1-30 μg/mL and R 2 coefficients were equal to 0.9922 and 0.9947 for zidovudine and tenofovir disoproxil fumarate, respectively. Extraction efficiency of the proposed method was compared with conventional salt-assisted liquid-liquid extraction. The results show that the proposed design has higher extraction efficiency than conventional salt-assisted liquid-liquid extraction. Finally, the proposed method was successfully applied for the determination of zidovudine and tenofovir disoproxil fumarate in plasma samples. K E Y W O R D Smicrochannel, salt-assisted liquid-liquid extraction, tenofovir disoproxil fumarate, zidovudine Article Related Abbreviations: ACN, acetonitrile; IPA, isopropanol; SALLE, salt-assisted liquid-liquid extraction; TDF, tenofovir disoproxil fumarate; THF, tetrahydrofuran; ZDV, zidovudine. unable to extract polar compounds. However, polar organic solvents such as acetonitrile (ACN), methanol, and acetone are suitable candidates for extraction of polar compounds. These organic solvents are water miscible and, thus, cannot be used for conventional LLE.The salt-assisted liquid-liquid extraction (SALLE) is a modified LLE method, which it used for extraction of polar compounds from the aqueous phase using the water-miscible organic solvents [1][2][3][4][5][6]. In the SALLE method, addition of an inorganic or organic salt into a mixture of aqueous sample and water-miscible organic solvent leads to the separation of organic solvent from the mixture and the formation of a twophase system [7][8][9][10][11]. Organic phase in the SALLE method

Simultaneous determination of paracetamol and caffeine in aqueous samples by ultrasound‐assisted emulsification microextraction coupled with high‐performance liquid chromatography

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Salting-Out Induced Liquid-Liquid Microextraction for Alogliptin Benzoate Determination in Human Plasma by HPLC/UV

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Preparation of multiwall carbon nanotube/urea‐formaldehyde nanocomposite as a new sorbent in solid‐phase extraction and its combination with deep eutectic solvent‐based dispersive liquid–liquid microextraction for extraction of antibiotic residues in honey

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