title: Maghemite nanoparticle-decorated hollow fiber electromembrane extraction combined with dispersive liquid-liquid microextraction for determination of thymol from Carum copticum.
abstract: BACKGROUND
  A novel technique using maghemite nanoparticle-decorated hollow fibers to assist electromembrane extraction is proposed. Electromembrane extraction combined with dispersive liquid-liquid microextraction (EME-DLLME) was applied for the extraction of thymol from Carum copticum, followed by gas chromatography with flame ionization detection (GC-FID).
  
  
  RESULTS
  The use of maghemite nanoparticle-decorated hollow fibers was found to improve the extraction efficiency of thymol significantly. Important operational parameters, including pH of acceptor phase, extraction time, voltage and temperature, were investigated and optimized. At the optimal conditions, linearity in the range 4-1800 µg L-1with a determination coefficient of 0.9996 was obtained. The limit of detection was 0.11 µg L-1(S/N = 3) and the pre-concentration factor was 200. The intra- and inter-day precision was 5.9 and 2.2% respectively. The intra- and inter-day accuracy was higher than 93.6%.
  
  
  CONCLUSIONS
  The results indicated that EME-DLLME/GC-FID is a useful technique for the extraction and determination of thymol in C copticum. © 2016 Society of Chemical Industry.
authors.affiliation: Department of Chemistry, University of Zabol, PO Box, 98615-538, Zabol, Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Khajeh
authors.affiliation: School of Pharmacy, University of Oslo, Oslo, Norway.
authors.forename: Stig
authors.initials: S
authors.lastname: Pedersen-Bjergaard
authors.affiliation: Department of Biology, University of Zabol, PO Box 98615-538, Zabol, Iran.
authors.forename: Mousa
authors.initials: M
authors.lastname: Bohlooli
authors.affiliation: Department of Chemistry, University of Zabol, PO Box, 98615-538, Zabol, Iran.
authors.forename: Afsaneh
authors.initials: A
authors.lastname: Barkhordar
authors.affiliation: Department of Chemistry, University of Zabol, PO Box, 98615-538, Zabol, Iran.
authors.forename: Mansour
authors.identifier: http://orcid.org/0000-0003-3231-0946
authors.initials: M
authors.lastname: Ghaffari-Moghaddam
mesh_terms: D029974:Carum / Q000737:chemistry*; D002849:Chromatography, Gas; D055664:Electrochemical Techniques / Q000379:methods*; D005410:Flame Ionization; D059627:Liquid Phase Microextraction / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008567:Membranes, Artificial; D013943:Thymol / Q000302:isolation & purification*
chemical_list: D058185:Magnetite Nanoparticles; D008567:Membranes, Artificial; D013943:Thymol
keywords: dispersive liquid-liquid microextraction; electromembrane extraction; maghemite nanoparticle-decorated hollow fiber; thymol