Data/hora: 19/06/2024 05:03:20

Biblioteca(s): 	Embrapa Agroindústria de Alimentos.	
Data corrente: 	08/01/2015	
Data da última atualização: 	18/02/2016	
Autoria: 	NEVES JUNIOR, A. C. V.; MELO, A.; PINHO, C.; CONEGLIAN, R. C. C.; SOARES, A. G.; FERREIRA, I. M. P. L. V. O.	
Afiliação: 	AUGUSTO C. V. NEVES JUNIOR, UFRJ; ARMINDO MELO, UNIVERSIDADE DO PORTO; CARINA PINHO, UNIVERSIDADE DO PORTO; REGINA C. C. CONEGLIAN, UFRRJ; ANTONIO GOMES SOARES, CTAA; ISABEL M. P. L. V. O. FERREIRA, UNIVERSIDADE DO PORTO.	
Título: 	Response surface methodology for optimization of cyanamide analysis by in situ derivatization and dispersive liquid-liquid microextraction.	
Ano de publicação: 	2014	
Fonte/Imprenta: 	Journal of chemometrics, v. 28, n. 9, p. 716-724, may 2014.	
DOI: 	10.1002/cem.2639	
Idioma: 	Inglês	
Conteúdo: 	Cyanamide is widely used for agricultural purposes; therefore, its residues can be found in water. A new method was developed for its quantification usingin situ derivatization with 2,6-dimethyl-4-quinolinecarboxylic acid N-hydroxysuccinimide ester followed by dispersive liquid–liquid microextraction (DLLME) and high-performance liquid chromatography/fluorescence analysis. Multivariate chemometric techniques were successfully used to obtain the optimum conditions for direct derivatization and DLLME extraction. Derivatization parameters and DLLME extraction conditions were optimized by a two-step design, 2k factorial design for screening, and central composite design for optimization. Best derivatization conditions were addition of 600?L of derivatizing reagent, a temperature of 4ºC, and pH 8.5, whereas for optimum extraction 800?L of solvent, 30% NaCl conc. w/v, and pH 3.8 were chosen. The analytical performance of the method for routine analysis was evaluated. Excellent linearity was achieved from 10 to 200?gL -1with a correlation factor of 0.9996. Precision ranged from 3.5% to 5.5% for intraday assays and 8.5% to 8.6% for interday assays. The mean recoveries performed on water from different origins (ground, river,sea, tap, and mineral) at three levels of concentration (20, 75, and 200?gL-1) ranged from 90.2% to 110.2%.	
Palavras-Chave: 	Análise quimiométrico; Chemometric analyses; Cyanamide; Derivazação in situ; Dispersão líquido-líquido; Dispersive liquid-liquid; In situ derivatization; Microextração.	
Thesaurus Nal: 	microextraction.	
Categoria do assunto: 	X Pesquisa, Tecnologia e Engenharia	
Registro original: 	Embrapa Agroindústria de Alimentos (CTAA)	
Exemplares: 	CTAA - (12477-1) - UPC - AP - PP - 2014/142 -  - 2014.00142 - DIS