Polymeric ionic liquid coatings versus commercial solid-phase microextraction coatings for the determination of volatile compounds in cheeses
| Autor: | Tien D. Ho, Verónica Pino, Jared L. Anderson, Ana M. Afonso, María J. Trujillo-Rodríguez, Honglian Yu, William T. S. Cole |
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| Rok vydání: | 2014 |
| Předmět: |
Detection limit
Volatile Organic Compounds Chromatography Polymers Chemistry Dodecane Extraction (chemistry) Ionic Liquids engineering.material Solid-phase microextraction Analytical Chemistry Partition coefficient chemistry.chemical_compound Coating Cheese Ionic liquid engineering Gas chromatography Solid Phase Microextraction |
| Zdroj: | Talanta. 121:153-162 |
| ISSN: | 0039-9140 |
| DOI: | 10.1016/j.talanta.2013.12.046 |
| Popis: | The extraction performance of four polymeric ionic liquid (PIL)-based solid-phase microextraction (SPME) coatings has been studied and compared to that of commercial SPME coatings for the extraction of 16 volatile compounds in cheeses. The analytes include 2 free fatty acids, 2 aldehydes, 2 ketones and 10 phenols and were determined by headspace (HS)-SPME coupled to gas chromatography (GC) with flame-ionization detection (FID). The PIL-based coatings produced by UV co-polymerization were more efficient than PIL-based coatings produced by thermal AIBN polymerization. Partition coefficients of analytes between the sample and the coating (Kfs) were estimated for all PIL-based coatings and the commercial SPME fiber showing the best performance among the commercial fibers tested: carboxen-polydimethylsyloxane (CAR-PDMS). For the PIL-based fibers, the highest K(fs) value (1.96 ± 0.03) was obtained for eugenol. The normalized calibration slope, which takes into account the SPME coating thickness, was also used as a simpler approximate tool to compare the nature of the coating within the determinations, with results entirely comparable to those obtained with estimated K(fs) values. The PIL-based materials obtained by UV co-polymerization containing the 1-vinyl-3-hexylimidazolium chloride IL monomer and 1,12-di(3-vinylimiazolium)dodecane dibromide IL crosslinker exhibited the best performance in the extraction of the select analytes from cheeses. Despite a coating thickness of only 7 µm, this copolymeric sorbent coating was capable of quantitating analytes in HS-SPME in a 30 to 2000 µg L(-1) concentration range, with correlation coefficient (R) values higher than 0.9938, inter-day precision values (as relative standard deviation in %) varying from 6.1 to 20%, and detection limits down to 1.6 µg L(-1). |
| Databáze: | OpenAIRE |
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