abstract
The design of poly(ionic liquids) (PILs) and their application as solid phase microextraction (SPME) fibers has been attracting enormous attention mainly due to the need for new SPME coating materials with improved analytical sensitivity. In this work, the tunability of Pits is explored by preparing different imidazolium monomers bearing benzyl, naphtylmethyl or pentyl pending groups that were subsequently co-polymerized, by reversible addition-fragmentation chain transfer (RAFT) polymerization with styrene. The obtained co-polymers showed excellent thermal stability up to 275 degrees C, with no melting point up to 250 degrees C. SPME fibers were prepared by an innovative approach based on layer-by-layer spray coating. The thin (< 10 mu m) SPME coatings were tested in GC-FID for the detection of volatile aromatic compounds such as benzene (B), toluene (T), ethylbenzene (E) and xylene (X) present in aqueous samples and the extraction parameters optimized. Superior results were obtained when comparing these LbL PILS-based SPME fibers with a commercial fiber composed of poly(dimethylsiloxane), with an increase in the detectable areas of 83%, 69%, 57% and 58% for B, T, E and X, respectively. Low relative standard deviations were obtained for the same fiber (< 5.6%) and also for different fibers (< 9.8%). Furthermore, a spiked soil sample was used to mimic a real contaminated soil sample and excellent recovery results, ranging from 67.0% to 102.2%, were obtained.
keywords
POLYMERIC IONIC LIQUID; STAINLESS-STEEL WIRE; GAS-CHROMATOGRAPHY; ALIPHATIC-HYDROCARBONS; POLY(IONIC LIQUIDS); SEPARATION SCIENCE; MASS-SPECTROMETRY; SORBENT COATINGS; RISK-ASSESSMENT; DRUG ANALYSIS
subject category
Chemistry; Engineering; Polymer Science
authors
Patinha, DJS; Pothanagandhi, N; Vijayakrishna, K; Silvestre, AJD; Marrucho, IM
our authors
Armando Jorge Domingues Silvestre
Full professor
David José Souto Patinha
PhD Student
Isabel Maria Delgado Jana Marrucho Ferreira
Full professoracknowledgements
David J. S. Patinha, is grateful to FCT (Fundacao para a Ciencia e a Tecnologia) for the PhD research grant SFRH/BD/97042/2013 and also the financial support from COST-Exil Project CM1206. The NMR data was acquired at CERMAX (Centro de Ressonancia Magnetica Antonio Xavier) which is a member of the National NMR network. This work was partially supported by PCT through Research Unit GREEN-it "Bioresources for Sustainability" (UID/Multi/04551/2013), CQE R&D Unit (UID/QUI/00100/2013) and the Associate Laboratory CICECO Aveiro Institute of Materials (UID/CTM/50011/2013).