title: Determination of nitrite in meat products and water using dapsone with combined spot test/diffuse reflectance on filter paper.
abstract: This paper describes a simple, portable and environmentally friendly procedure for the determination of nitrite by combined spot test/diffuse reflectance spectroscopy on filter-paper. The method is based on the diazotization reaction of dapsone (4,4'-diamino-diphenyl sulphone, DAP) and (naphthyl)ethylenediamine hydrochloride (NED) with nitrite in acidic medium, yielding a coloured compound on the surface of a filter paper. Experimental design methodologies were used to optimise the measurement conditions. The reflectometric measurements were carried out at 545 nm and the linear range obtained was 0.29-5.0 mg L(-1) of nitrite (R=0.997), with detection and quantification limits of 0.09 and 0.29 mg L(-1), respectively. The proposed method was applied successfully to the analysis of nitrite in meat products and well water samples.
authors: Instituto de Química, Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Araraquara, São Paulo, Brazil.
authors: Vitor Hugo Marques
authors: VH
authors: Luiz
authors: Leonardo
authors: L
authors: Pezza
authors: Helena Redigolo
authors: HR
authors: Pezza
mesh_terms: D003622:Dapsone / Q000737:chemistry; D008461:Meat Products / Q000032:analysis*; D009573:Nitrites / Q000032:analysis*; D013057:Spectrum Analysis / Q000295:instrumentation / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D009573:Nitrites; D014874:Water Pollutants, Chemical; D003622:Dapsone