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Bianchi F.,University of Parma | Bisceglie F.,University of Parma | Dugheri S.,Laboratorio Of Igiene E Tossicologia Industriale | Arcangeli G.,Laboratorio Of Igiene E Tossicologia Industriale | And 6 more authors.
Journal of Chromatography A | Year: 2014

Wearable solid phase microextraction (SPME) devices consisting in necklaces and pins were developed for the environmental monitoring of ketamine in recreational places using ionic liquid as coating. SPME fibers obtained using both monocationic and dicationic polymeric ionic liquids were characterized in terms of morphology, film thickness, thermal stability and pH resistance. An average thickness of 30±5μm, an excellent thermal stability until 350°C and a very good fiber-to-fiber and batch-to-batch repeatability with RSD lower than 4% were some of the features of the developed coatings. A quantitation limit (LOQ) of 0.05mg/m3 with a sampling time of 1min proved the feasibility of the developed method for the quantitation of ketamine in air at low concentration levels. Finally, the capabilities of the fibers for the rapid SPME sampling of ketamine in recreational places were proved obtaining extraction efficiencies at least two-fold higher than those obtained using commercial devices and extraction recoveries ranging from 84.2±3.3% to 93.6±2.6% (n=3). © 2014 Elsevier B.V. Source

Bianchi F.,University of Parma | Bedini A.,University of Parma | Riboni N.,University of Parma | Pinalli R.,University of Parma | And 4 more authors.
Analytical Chemistry | Year: 2014

A selective cavitand-based solid-phase microextraction coating was synthesized for the determination of nitroaromatic explosives and explosive taggants at trace levels in air and soil. A quinoxaline cavitand functionalized with a carboxylic group at the upper rim was used to enhance selectivity toward analytes containing nitro groups. The fibers were characterized in terms of film thickness, morphology, thermal stability, and pH resistance. An average coating thickness of 50 (±4) μm, a thermal stability until 400 °C, and an excellent fiber-to-fiber and batch to batch repeatability with RSD lower than 4% were obtained. The capabilities of the developed coating for the selective sampling of nitroaromatic explosives were proved achieving LOD values in the low ppbv and ng kg-1 range, respectively, for air and soil samples. © 2014 American Chemical Society. Source

Risticevic S.,University of Waterloo | Chen Y.,Supelco | Kudlejova L.,University of Waterloo | Vatinno R.,University of Waterloo | And 4 more authors.
Nature Protocols | Year: 2010

Ever since the invention of gas chromatography (GC), numerous efforts within the chromatographic community have been directed toward the development of fast GC methods. However, the developments in high-speed GC technologies have simultaneously created demand for the availability of compatible detection and sample preparation methods, so that the speed of the overall analytical process is increased. Solid phase micro extraction (SPME) is a sample preparation technique developed to address the need for rapid sample preparation. Therefore, the objective of this protocol is to outline recent developments in SPME technology that can be applied toward high-throughput automated qualitative and quantitative analyses of volatile and semivolatile compounds in wine samples. The use of this protocol facilitates routine high-throughput determinations of 200-500 analytes of different physicochemical properties with SPME step requiring only 10-15 min per sample. © 2009 Nature Publishing Group. Source

Goto H.,Japan Food Research Laboratories | Goto H.,Mimasaka University | Shionoya N.,Japan Food Research Laboratories | Sugie M.,Japan Food Research Laboratories | And 5 more authors.
Journal of Oleo Science | Year: 2012

We developed a novel pre-separation method of trans fatty acids (TFAs) using a silver-ion cartridge column and GC. As a preliminary study, a mixture of fatty acid methyl esters consisting of saturated, cis-unsaturated, and trans-unsaturated fatty acids was dissolved in dichloromethane and loaded onto a Bond Elut SCX ion-exchange cartridge column that was converted to the silver-ion form. The column was then eluted with dichloromethane to obtain the saturated fatty acids, dichloromethane/ethyl acetate (90/10) for the trans mono-ene, dichloromethane/ethyl acetate (65/35) for the cis mono-ene, dichloromethane/ acetone (60/40) for the trans di-ene, and acetone/acetonitrile (80/20) for the others. Satisfactory separation of the cis/trans isomers was confi rmed by GC analysis. To generalize this technique, the elution conditions of the ready-to-use Discovery Ag-ION SPE cartridge column were also optimized. Both cartridge columns had good separation, recovery, and repeatability. Peer laboratory verification was carried out between two laboratories using different production lots of the ready-to-use cartridge column, and the robustness of the product and reproducibility of the method were found to be satisfactory. This technique is therefore a powerful tool not only for routine analyses of TFAs in oils, fats, and foods but also for detailed analyses of TFAs in various research fi elds. Source

Martinez Bueno M.J.,University of Almeria | Herrera S.,University of Almeria | Ucles A.,University of Almeria | Aguera A.,University of Almeria | And 6 more authors.
Analytica Chimica Acta | Year: 2010

This paper describes the development of an analytical procedure to determine malachite green (MG) residues in salmon samples using molecularly imprinted polymers (MIPs) as the extraction and clean-up material, followed by liquid chromatography-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS). MG and two structurally related compounds, crystal violet (CV) and brilliant green (BG) were employed for the selectivity test. The imprinted polymers exhibited high binding affinity for MG, while CV and BG showed less binding capacity: 47% and 34%, respectively. The recovery values of MG in salmon samples fortified with leucomalachite green (LMG) were determined by measuring the amount of MG in the sample, after carrying out the oxidation reaction with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), which converts the LMG back into chromic-form. The average recovery of MG in spiked salmon muscle over the concentration range 1-100ngg-1 was 98% with a relative standard deviation value (R.S.D.) below 12%. The method detection limits (MDLs) obtained for MG, CV, BG and their leuco-metabolites were in the range of 3-20ngkg-1 (ppt). © 2010 Elsevier B.V. Source

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