پديدآورندگان :
Badiee Hamid Department of Chemistry, Faculty of Science, University of Guilan, University of Campus 2, Rasht, Iran / Environmental Science Research Laboratory, Department of Environmental Science, Faculty of Science, University of Zanjan, 45371-38791, Zanjan, Iran , Zanjanchi Mohammad Ali Department of Chemistry, Faculty of Science, University of Guilan, University of Campus 2, Rasht, Iran / Department of Chemistry, Faculty of Science, University of Guilan, Rasht, 41335-1914, Iran , Zamani Abbasali Zamani@znu.ac.ir Environmental Science Research Laboratory, Department of Environmental Science, Faculty of Science, University of Zanjan, 45371-38791, Zanjan, Iran; , Fashi Armin Environmental Science Research Laboratory, Department of Environmental Science, Faculty of Science, University of Zanjan, 45371-38791, Zanjan, Iran
كليدواژه :
Water , Environment , Pollution , Cationic surfactant
چكيده فارسي :
Nitrite is a common surface and groundwater contaminant that causes acute and chronic toxic effects in humans and animals. Thus, monitoring the concentration of nitrite in water sample sources is one of the major analytical tasks of water quality control management. Several methods including, electrochemical technique, fluorometric method, and paper microfluidic device have been reported for the determination of the nitrite ion in different matrices [1, 2]. Recently, a novel form of hollow fiber liquid phase microextraction (HF–LPME) namely solvent bar microextraction (SBME) has been introduced. SBME provides higher pre-concentration factor and the enhanced mass transfer of analyte from donor solution into the extraction solvent in comparison with HF-LPME due to the random and free movement of the fiber [3, 4]. A new design introduced for the preconcentration of nitrite in environmental water samples using surfactant-assisted two phase solvent stir-bar microextraction (SSBME), followed by microcell UV–Vis spectrophotometry. The method relies on the reaction of nitrite with iodide excess in acidic donor phase to form triiodide, and then its extraction into organic acceptor phase using tetrabutylammonium bromide (TBAB) as a cationic surfactant. The main parameters in detail that affect the triiodide formation and the extraction efficiency (SSBME procedure) investigated and optimized. Under the optimized conditions (extraction time 8min., stirring rate 300 rpm., donor phase 50 mL, acceptor phase 10 mL, organic solvent 1- Octanol) the proposed method provided good linearity in the range of 16 to 1000 ng mL−1, satisfactory repeatability (RSDs 6 %) with preconcntration factor of 250 fold. Finally, the developed method successfully applied to the determination of nitrite in environmental water samples. The proposed method has some advantages in comparison with the other methods for nitrite determination including, simplicity of operation, generation of little or no waste, low cost of the extraction device, no memory effect due to the single-used and disposable nature of hollow fiber, low solvent consumption and environmental benignity with wide application prospects in trace analysis.
