title: Extraction of pyridine derivatives from human urine using electromembrane extraction coupled to dispersive liquid-liquid microextraction followed by gas chromatography determination.
abstract: 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 1mL 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<RSD%<5.3) were obtained in different matrices. The method offered a good linearity with coefficient of determination greater than 0.9948 and was utilized for determination and quantification of pyridine compounds in smokers׳ urine samples. The proposed technique can be introduced as a simple, fast and inexpensive method for diagnosis of smokers.
authors.affiliation: Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Arjomandi-Behzad
authors.affiliation: Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran. Electronic address: yyamini@modares.ac.ir.
authors.forename: Yadollah
authors.initials: Y
authors.lastname: Yamini
authors.affiliation: Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Rezazadeh
mesh_terms: D000468:Alkalies / Q000737:chemistry; D002849:Chromatography, Gas / Q000379:methods*; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D004987:Ethers / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D059627:Liquid Phase Microextraction / Q000379:methods*; D008567:Membranes, Artificial; D011725:Pyridines / Q000737:chemistry / Q000302:isolation & purification* / Q000652:urine*; D015203:Reproducibility of Results; D012907:Smoking; D012996:Solutions / Q000737:chemistry
chemical_list: C519952:2-nitrophenyl octyl ether; D000468:Alkalies; D004987:Ethers; D008567:Membranes, Artificial; D011725:Pyridines; D012996:Solutions; C023666:pyridine
keywords: Dispersive liquid–liquid microextraction; Electromembrane; Pyridine derivatives; Urine