A novel poly(3,4-ethylenedioxythiophene)-ionic liquid composite coating for the headspace solid-phase microextraction and gas chromatography determination of several alcohols in soft drinks

• A poly(3,4-ethylenedioxythiophene)-ionic liquid composite coating was prepared.
• It showed nodular structure and had large surface.
• It presented high thermal stability, durability and extraction efficiency for alcohols.
• This is a new way to make use of monomer and ionic liquid to prepare SPME fibers.

A novel poly(3,4-ethylenedioxythiophene)-ionic liquid (i.e., 1-hydroxyethyl-3-methyl imidazolium-bis[(trifluoromethyl)sulfonyl]imide) composite film was electrodeposited on a Pt wire for headspace solid-phase microextraction. The film showed nodular structure and had large specific surface. In addition, it displayed high thermal stability (up to 300 °C) and durable property (could be used for more than 200 times). Coupled with gas chromatography-flame ionization detection, the resulting fiber was applied to the headspace solid-phase microextraction and determination of several alcohols (i.e., linalool, nonanol, terpineol, geraniol, decanol and dodecanol). It presented higher extraction capability in comparison with the poly(3,4-ethylenedioxythiophene) and commercial polydimethylsiloxane/divinylbenzene fiber. Under the optimized conditions, the linear ranges exceeded three magnitudes with correlation coefficients above 0.9952 and the low limits of detection were 34.2–81.3 ng L−1. For different alcohols the repeatabilities (defined as RSD) were <5.8% and <7.8% for single fiber (n = 5) and fiber-to-fiber (n = 4), respectively. The proposed method was applied to the determination of these alcohols in real samples with acceptable recoveries from 81.1% to 106.6%.

Electrodeposited poly(3,4-ethylenedioxythiophene)-ionic liquid composite coating showed nodular structure and had large surface, it presented high thermal stability, durability and extraction efficiency for alcohols.Figure optionsDownload as PowerPoint slide