Deep eutectic solvent-based liquid-phase microextraction coupled with reversed-phase high-performance liquid chromatography for determination of α-, β-, γ-, and δ-tocopherol in edible oils

• Published in: Analytical and bioanalytical chemistry Vol. 413; no. 2; pp. 577 - 584
• Main Authors: Xie, Qilong, Xia, Ming, Sun, Dekui, Cao, Jiangping, Xiao, Yong, Lin, Mingui, Hou, Bo, Jia, Litao, Li, Debao
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2021; Springer Nature B.V
• Subjects: Ammonium; Ammonium salts; Analytical Chemistry; Biochemistry; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Chromatography; Detection limits; Edible oils; Ethanol; Extractants; Food Science; High performance liquid chromatography; Homology; Laboratory Medicine; Liquid chromatography; Liquid phases; Monitoring/Environmental Analysis; Oils & fats; Quaternary ammonium salts; Research Paper; Salts; Solvents; Tetrabutylammonium chloride; Tocopherol; Tocopherols; Tocopherols; Liquid-phase microextraction; Edible oils; Deep eutectic solvent
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-020-03029-1

For simultaneous analysis of four fat-soluble tocopherols (α-, β-, γ-, and δ-) in edible oils, an efficient and green method using deep eutectic solvent-based liquid-phase microextraction (DES-LPME) coupled with reversed-phase high-performance liquid chromatography (RP-HPLC) was developed. The DESs formed by different quaternary ammonium salts and ethanol were used as the extractants. Tetrabutylammonium chloride (TBAC)-ethanol DES at a molar ratio of 1:2 achieved the best extraction efficiency. Under the optimized conditions, the detection limits were in the range of 2.1–3.0 ng mL −1 . The intra-day and inter-day repeatability were in the ranges of 3.9–5.3% and 4.8–7.1%, respectively, and the recoveries for the real samples varied from 80.7% to 105.4%. The developed method was successfully employed for the determination of all four tocopherol homologues with an RP-HPLC system containing a COSMOSIL π-NAP column in five edible oils collected locally. Graphical abstract