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چکیده
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Aliphatic amines are important metabolitic intermediates in decomposition processes and are distributed in environmental waters. These compounds can be found in biological fluid, environmental samples and industrial process stream, often at trace levels. Direct aqueous injection is sensitive only to the parts per million level. These highly polar and basic amines are very soluble in water, a fact which in the past has been a barrier to the development of an efficient method for extracting these amines into an organic solvent or onto a solid phase adsorbent. In this work, the capability of a new electro-solid phase microextraction is investigated as a solvent-free introduction of underivatized aliphatic amines into GC. A pencil lead used previously for solid-phase microextraction (SPME) acts as both an adsorbent and a working electrode. The working electrode was immersed in pH 8 borate buffer solution and a -1.90 V potential versus SCE (saturated calomel electrode) was applied. The electrode is removed from the solution, then introduced into the GC inlet where the amines are thermally desorbed, transported to the column, separated and detected. Calibration graph was liner in the range 0.4-10 µg mL-1; the detection limit was under 0.32 ppm using a flame ionization detector. This method can be developed to the extraction and concentration of various pharmaceutical compounds with amine structure from liquid samples.
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