Ionic liquid supported on an electrodeposited polycarbazole film for the headspace solid‐phase microextraction and gas chromatography determination of aromatic esters

A polycarbazole film was electrodeposited on a stainless‐steel wire from a solution of N,N‐dimethylformamide/propylene carbonate (1:9 v/v) containing 0.10 M carbazole and 0.10 M tetrabutylammonium perchlorate. The obtained polycarbazole fiber was immersed into an ionic liquid (1‐hydroxyethyl‐3‐methyl imidazolium bis[(trifluoromethyl)sulfonyl]imide) solution (in dimethylsulfoxide) for 30 min, followed by drying under an infrared lamp. The resulting polycarbazole/ionic liquid fiber was applied to the headspace solid‐phase microextraction and determination of aromatic esters by coupling with gas chromatography and flame ionization detection. Under the optimized conditions, the limits of detection were below 61 ng/L (S/N = 3) and the linear ranges were 0.061−500 μg/L with correlation coefficients above 0.9876. The relative standard deviations were below 4.8% (n = 5) for a single fiber, and below 9.9% for multi‐fiber (n = 4). This fiber also exhibited good stability. It could be used for more than 160 times of headspace solid‐phase microextraction and could withstand a high temperature up to 350°C.