Electrodeposition of poly(3,4-ethylenedioxythiophene) on a stainless steel wire for solid phase microextraction and GC determination of some esters with high boiling points

In this work, 3,4-ethylenedioxythiophene (EDOT) emulsion is prepared by ultrasonication agitation and poly(3,4-ethylenedioxythiophene) (PEDOT) coating is fabricated on a stainless steel wire by electrochemical method from a 0.10 M sodium dodecylbenzenesulfonate aqueous solution containing EDOT. The coating is characterized by scanning electron microscopy and Fourier transform infrared spectrophotometry, and it presents cauliflower-like structure. When the resulted PEDOT/steel fiber is used for the headspace solid phase-microextraction of some esters (i.e. methyl anthranilate, dimethyl phthalate, ethyl-o-aminobenzoate, methyl laurate and diethyl phthalate) and their GC detection, the limits of detection (LOD) are ca. 7.8–31 ng L−1 (S/N=3) and the linear ranges are 0.25–800 μg L−1. The fiber shows high thermal stability (up to 320 °C), good reproducibility and long lifetime (more than 183 times). It also has good chemical stability. After it is immersed in acid, alkali and dichloromethane for 4 h its extraction efficiency remains almost unchanged. Besides esters the fiber also exhibits high extraction efficiency for alcohols and aromatic compounds.