Affiliation:
1. Department of Physical Education Shanghai Lixin University Accounting and Finance Shanghai China
2. Department of Physical Education Donghua University Shanghai China
3. Faculty of Health Sciences and Sport University of Stirling Stirling UK
4. Beijing Yiboni Technology Co., Ltd Beijing China
5. College Sport Arts Guangzhou Sport University Guangzhou China
Abstract
In this work, an easy, safe, simple, and efficient pH‐switchable deep eutectic solvents (DESs)‐based liquid phase microextraction followed by high‐performance liquid chromatography‐diode array detector analysis was developed for the determination of 1,3‐dimethylamylamine (DMAA). The switchability of the obtained DESs was investigated by changing the pH. Then the best‐selected DES was characterized and the application of the selected DES in the extraction of DMAA from sports nutrition and bodybuilding supplements was investigated. The DES synthesized from l‐menthol: oleic acid in a molar ratio of 1:2 had the highest efficiency in the extraction of the target compound. Under the optimum conditions, (50 µL of DES, 100 µL of 4 mol/L KOH, 100 µL of 4 mol/L HCl, extraction time of 40 s and without salt addition) the calibration graph was linear in the range of 0.05–100 µg/kg and limit of detection was 0.02 µg/kg. The relative standard deviations including intra‐day and inter‐day for 10.0 µg/kg of DMAA in real samples were 2.7% (n = 7) and 5.3% (n = 7), respectively. The enrichment factor and percentage extraction recovery of the method were 283 and 85%, respectively. The relative recoveries for DMAA in different samples were in the range of 90%–109%.
Funder
China Scholarship Council