Data/hora: 23/06/2024 13:00:29

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