Ionic liquids based dispersive liquid-liquid microextraction coupled to gas chromatography for determination of aromatic hydrocarbons

The advantages of dipersive liquid-liquid microextraction(DLLME) coupled to gas chromatography are simplicity of operation,rapidity,low cost with high recovery rate and enrichment factor.Ionic liquids based DLLME coupled to gas chromatography for the simultaneous determination of diversified aromatic hydrocarbons was developed in this paper.The sample injection part of gas chromatographic instrument was modified to avoid the ionic liquid leaking into the chromatographic column.The parameters affecting extraction efficiency such as extractant,dispersive solvent,volume of the solvent and extraction time were studied.Under the optimum conditions,the enrichment factors ranged from 31 to 105.The linear range for the determination was 1-100 μg/L and the limits of detection were from 0.2 to 0.5 μg/L(S /N = 3),with the correlation coefficients(r) varying from 0.991 to 0.995.Using ionic liquid as extractantcan can effectively reduce the interference of solvent peak and enhance the extraction efficiency as well.