Zwitterionic polymeric ionic liquid-based sorbent coatings in solid phase microextraction for the determination of short chain free fatty acids

Idaira Pacheco-Fernández; María J Trujillo-Rodríguez; Kosuke Kuroda; Andrew L Holen; Mark B Jensen; Jared L Anderson

doi:10.1016/j.talanta.2019.03.073

Zwitterionic polymeric ionic liquid-based sorbent coatings in solid phase microextraction for the determination of short chain free fatty acids

Talanta. 2019 Aug 1:200:415-423. doi: 10.1016/j.talanta.2019.03.073. Epub 2019 Mar 19.

Authors

Idaira Pacheco-Fernández¹, María J Trujillo-Rodríguez², Kosuke Kuroda³, Andrew L Holen⁴, Mark B Jensen⁴, Jared L Anderson⁵

Affiliations

¹ Departamento de Química (Unidad Departamental de Química Analítica), Universidad de La Laguna, La Laguna, Tenerife 38206, Spain; Department of Chemistry, Iowa State University, Ames, IA 50011, USA.
² Department of Chemistry, Iowa State University, Ames, IA 50011, USA.
³ Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
⁴ Department of Chemistry, Concordia College, Moorhead, MN 56562, USA.
⁵ Department of Chemistry, Iowa State University, Ames, IA 50011, USA. Electronic address: andersoj@iastate.edu.

PMID: 31036204
DOI: 10.1016/j.talanta.2019.03.073

Abstract

Five different zwitterionic sorbent coatings based on polymeric ionic liquids (PILs) were developed by the on fiber UV co-polymerization of the zwitterionic monomers 1-vinyl-3-(alkylsulfonate)imidazolium or 1-vinyl-3-(alkylcarboxylate)imidazolium and different dicationic ionic liquid (IL) crosslinkers. The developed sorbent coatings were applied in headspace solid-phase microextraction in combination with gas chromatography-mass spectrometry for the determination of short chain free fatty acids in wine. The sorbent coatings were found to extract these analytes via a non-competitive extraction mechanism. The methodology was optimized for the two best zwitterionic PIL coatings and compared to the commercially-available carboxen/polydimethylsiloxane (CAR/PDMS) and polyacrylate (PA) fibers. The sorbent coating based on the 1-vinyl-3-(propanesulfonate)imidazolium IL (Fiber 1) was more sensitive than PA while providing similar limits of detection to CAR/PDMS for the determination of analytes in a diluted synthetic wine sample. At the same time, Fiber 1 required lower extraction times (only 20 min versus 60 min for CAR/PDMS and 40 min for PA), exhibited higher reproducibility (with relative standard deviation lower than 8.9% for a spiked level of 7 µM) and was more tolerant to ethanol present within the sample. The zwitterionic PILs were also applied for the analysis of red wine, and the results were in agreement with those obtained for CAR/PDMS. The analytes were detected and quantified in the concentration range from 0.18 ± 0.03 mg L^-1 to 4.8 ± 0.9 mg L^-1, depending on the analyte and fiber.

Keywords: Polymeric ionic liquids; Short chain free fatty acids; Solid-phase microextraction; Wine; Zwitterionic liquid.