Extraction of pyridine derivatives from human urine using electromembrane extraction coupled to dispersive liquid–liquid microextraction followed by gas chromatography determination

•Electromembrane extraction was coupled with dispersive liquid–liquid microextraction.•Method was applied for extraction pyridine derivatives from urine and water samples.•Effective parameters on efficiency of the method were optimized by experimental design.•Preconcentration factors in the range of 40–263 and good repeatabilities were obtained.•The method can be introduced as a fast and inexpensive method for diagnosis of smokers.

In the present work, some of pyridine derivatives were analyzed for the first time in complicated biological fluids by coupling electromembrane extraction with dispersive liquid–liquid microextraction (EME–DLLME). 3-Methylpyridine, 2,4-lutidine, quinoline and 4-dimethylaminopyridine (DMAP) were extracted from urine and water samples. Effective parameters on the efficiencies of EME and DLLME were optimized by one variable at a time method and face-centered central composite design (FCCCD), respectively. The supported liquid phase (SLM) employed for the extraction of the analytes was a mixture of 90% 2-nitrophenyl octyl ether (NPOE) and 10% di-(2-ethylhexyl) phosphate (DEHP) which was immobilized in the pores of a piece of hollow fiber. An electric field was applied to carry over the analytes into acceptor solution. The acceptor solution was transferred to 1 mL of an alkaline solution (pH=13) and then DLLME procedure was performed. Preconcentration factors in the range of 40–263 and satisfactory repeatabilities (2.3

Graphical abstractIn the present study electromembrane extraction coupled to dispersive liquid–liquid microextraction was applied for extraction of ultra-trace amounts of some pyridine derivatives from complicated biological fluids. Figure optionsDownload full-size imageDownload as PowerPoint slide