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چکیده
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Pawliszyn first described the solvent free extraction technique, solid phase microextraction (SPME), IN THE LATE 1980S. SPME is based on the partitioning of analyte between an extracting phase; usually a polymeric material immobilized on a fused silica fiber, and a sample. Absorption is carried out for a well-defined time or until equilibrium is reached. In gas chromatography (GC), exposing the fiber injection port thermally desorbs the analytes. If coupled to high performance liquid chromatography (HPLC), the analytes are resolved in an organic solvent. The efficiency of polyaniline (PANI) coated gold wire was investigated as a fiber for solid phase microextraction (SPME). Aniline monomers were electrpolymerized on gold wires by constant current applying in acetate buffer containing NaClO4 as supporting electrolyte for 30 minute. These fibers were used for the extraction of some phenolic compounds from gaseous samples. The extracted analytes were transferred to a GC injectior using an (in house designed) SPME syringe. The results obtained prove the ability of PANI fiber for sampling of organic compounds from gaseous samples. In this work, the optimum conditions for preparation and conditioning of fibers and the extraction of analytes from gaseous samples were obtained. In the optimum conditions, one fiber was used in several equal analyses and the relative standard deviations (RSD) were below 7% (n=5). However, fiber to fiber reproducibility was 9% (n=5).
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