Electrospinning preparation of solid phase microextraction fibers based on polyamide
Polymeric nanofibers present high surface-to-volume ratios which make them so attractive in extraction procedures since their high superficial area increases the potential interaction analyte-sorbent with positive thermodynamic and kinetic connotations. The synthesis and preparation of these nanofibers can be achieved in the lab by electrospinning. This process is based on the application of a high voltage to a polymer solution in order to produce a thin liquid jet which is finally ejected. First of all, a precursor of the nanofiber polymer is dissolved in an appropriate solvent to produce a viscose solution which is introduced in a syringe for its dispensation at a fixed and controlled velocity. Later on, an electric field (high voltage) is established between the syringe needle and a collector which acts also as the receptor of the produced nanofibers. As a consequence of this electric field, the mutual charge repulsion on the surface of the liquid overcomes the surface tension...