title: Micell-mediated extraction for the spectrophotometric determination of nitrite in water and biological samples based on its reaction with p-nitroaniline in the presence of diphenylamine.
abstract: A cloud point extraction process using the nonionic surfactant Triton X-100 to extract nitrite from aqueous solution was investigated. The method is based on the color reaction of nitrite with p-nitroaniline in the presence of diphenylamine in acid media and micell-mediated extraction of an azo product. The optimal extraction and reaction conditions (e.g., acid concentration, reagent concentration, effect of time) were studied, and the analytical characteristics of the method (e.g., limit of detection, linear range, molar absorptivity, preconcentration, and improvement factors) were obtained. Linearity was obeyed in the range of 2-40 ng ml(-1) of nitrite ion. The detection limit of the method is 0.87 ng ml(-1) of nitrite ion. The interference effect of some anions and cations was also tested. The method was applied to the determination of nitrite in tap water, waste water, and human urine samples.
authors.affiliation: Department of Chemistry, Faculty of Sciences, Bu-Ali Sina University, Hamadan 65174, Iran. afkhami@basu.ac.ir
authors.forename: Abbas
authors.initials: A
authors.lastname: Afkhami
authors.forename: Morteza
authors.initials: M
authors.lastname: Bahram
authors.forename: Somayeh
authors.initials: S
authors.lastname: Gholami
authors.forename: Zahra
authors.initials: Z
authors.lastname: Zand
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D004159:Diphenylamine / Q000737:chemistry*; D006801:Humans; D008823:Micelles; D015394:Molecular Structure; D009573:Nitrites / Q000737:chemistry* / Q000302:isolation & purification*; D013057:Spectrum Analysis / Q000379:methods*; D013464:Sulfuric Acids / Q000494:pharmacology; D014556:Urine / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D000814:Aniline Compounds; D008823:Micelles; D009573:Nitrites; D013464:Sulfuric Acids; D014867:Water; C019498:4-nitroaniline; D004159:Diphenylamine; C033158:sulfuric acid