Data/hora: 22/06/2024 03:13:21

Biblioteca(s): 	Embrapa Pecuária Sudeste.	
Data corrente: 	26/06/2009	
Data da última atualização: 	15/03/2023	
Autoria: 	GONZALEZ, M. H.; SOUZA, G. B. D.; OLIVEIRA, R. V. DE; FORATO, L. A.; NÓBREGA, J. A.; NOGUEIRA, A. R. de A.	
Afiliação: 	MÁRIO HENRIQUE GONZALEZ, UFSCAR; GILBERTO BATISTA DE SOUZA, CPPSE; REGINA V. DE OLIVEIRA, UFSCAR; LUCIMARA A. FORATO, UFSCAR; JOAQUIM A. NÓBREGA, UFSCAR; ANA RITA DE ARAUJO NOGUEIRA, CPPSE.	
Título: 	Microwave-assisted digestion procedures for biological samples with diluted nitric acid: identification of reaction products.	
Ano de publicação: 	2009	
Fonte/Imprenta: 	Talanta, v. 79, n. 2, p. 396-401, jul. 2009.	
DOI: 	10.1016/j.talanta.2009.04.001	
Idioma: 	Inglês	
Conteúdo: 	Microwave-assisted sample preparation using diluted nitric acid solutions is an alternative procedure for digesting organic samples. The efficiency of this procedure depends on the chemical properties of the samples and in this work it was evaluated by the determination of crude protein amount, fat and original carbon. Soybeans grains, bovine blood, bovine muscle and bovine viscera were digested in a cavity-microwave oven using oxidant mixtures in different acid concentrations. The digestion efficiency was evaluated based on the determination of residual carbon content and element recoveries using inductively coupled plasma optical emission spectrometry (ICP OES). In order to determine the main residual organic compounds, the digests were characterized by nuclear magnetic resonance ((1)H NMR). Subsequently, studies concerning separation of nitrobenzoic acid isomers were performed by ion pair reversed phase liquid chromatography using a C18 stationary phase, water:acetonitrile:methanol (75:20:5, v/v/v)+0.05% (v/v) TFA as mobile phase and ultraviolet detection at 254 nm. Sample preparation based on diluted acids proved to be feasible and a recommendable alternative for organic sample digestion, reducing both the reagent volumes and the variability of the residues as a result of the process of decomposition. It was shown that biological matrices containing amino acids, proteins and lipids in their composition produced nitrobenzoic acid isomers and other organic compounds after cleavage of chemical bonds.	
Palavras-Chave: 	Biological samples; Diluted nitric acid; Nitrobenzoic acid isomers; Sample preparation.	
Thesaurus Nal: 	high performance liquid chromatography.	
Categoria do assunto: 	W Química e Física	
URL: 	http://ainfo.cnptia.embrapa.br/digital/bitstream/item/38657/1/PROCI-2009.00018.pdf	
Registro original: 	Embrapa Pecuária Sudeste (CPPSE)	
Exemplares: 	CPPSE - (18354-1) - UPC - AP - DD - PROCI-2009.00018 - GON - 2009.00018 - DIS