Simultaneous derivatization and extraction of anilines in waste water with dispersive liquid–liquid microextraction followed by gas chromatography–mass spectrometric detection

The one-step derivatization and extraction technique for the determination of anilines in river water by dispersive liquid–liquid microextraction (DLLME) is presented. In this method the anilines are extracted by DLLME and derivatized with pentafluorobenzaldehyde (PFBAY) in aqueous solution simultaneously. In this derivatization/extraction method, 0.5 ml acetone (disperser solvent) containing 10 μl chlorobenzene (extraction solvent) and 30 g/l pentafluorobenzaldehyde (PFBAY) dissolved in methanol was rapidly injected by syringe into 5 ml aqueous sample (pH 4.6). Within 20 min the analytes extracted and derivatized were almost finished. After centrifugation, 2 μl sedimented phase containing enriched analytes was determined by GC–MS. The effects of extraction and disperser solvent type and their volume, pH value of sample solution, derivatization and extraction time, derivatization and extraction temperature were investigated. Linearity in this developed method was ranging from 0.25 to 70 μg/l, and the correlation coefficients (R2) were between 0.9955 and 0.9989, and reasonable reproducibility ranging from 5.8 to 11.8% (n = 5). Method detection limits (MDLs) ranged from 0.04 to 0.09 μg/l (n = 5).