Simultaneous determination of polar and apolar compounds in environmental samples by a polyaniline/hydroxyl multi-walled carbon nanotubes composite-coated stir bar sorptive extraction coupled with high performance liquid chromatography

Developing novel coatings for stir bar sorptive extraction (SBSE) is essential for extending the application of SBSE. Herein, a polyaniline/hydroxyl multi-walled carbon nanotubes (PANi/MWCNTs-OH) composite-coated stir bar was prepared via the adhesion technique for the simultaneous extraction of polar and apolar compounds, and a novel method of PANi/MWCNTs-OH-coated SBSE coupled with high performance liquid chromatography-ultraviolet detection (HPLC-UV) was proposed, To test the extraction performance of PANi/MWCNTs-OH-coated stir bar, phenols, non-steroidal anti-inflammatory drugs, and polychlorinated biphenyls were selected as representatives for polar, semi-polar and apolar compounds, respectively. High enrichment factors (EFs) ranged from 20.4 to 60.4-fold (theoretical EF, 100-fold) for target analytes were achieved, indicating that the proposed method is applicable in simultaneous analysis of the compounds with different polarities. The prepared PANi/MWCNTs-OH-coated stir bar has a good preparation reproducibility and can be reused for 20 times. The limits of detection (LODs, SIN = 3) were found to be in the range of 0.09-0.81 mu g/L. To validate the applicability, the proposed method was successfully applied to the analysis of eight target analytes in Yangtze River water after filtration and in the extract from sediment samples. (C) 2015 Elsevier B.V. All rights reserved.