Optimization of a method for determination of phenolic acids in exotic fruits by capillary electrophoresis

Autor(es)

Fukuji, Tatiana S. ; Tonin, Fernando G. ; Tavares, Marina F. M.

• Tipo de documento: Artigo Científico
• Fonte: Journal of Pharmaceutical and Biomedical Analysis; v. 51, n. 2, p. 9-pg., 2010-01-20.

Resumo

In this work, the separation of nine phenolic acids (benzoic, caffeic, chlorogenic, p-coumaric, ferulic, gallic, protocatechuic, syringic, and vanillic acid) was approached by a 32 factorial design in electrolytes consisting of sodium tetraborate buffer(STB) in the concentration range of 10-50 mmol L-1 and methanol in the volume percentage of 5-20%. Derringer's desirability functions combined globally were tested as response functions. An optimal electrolyte composed by 50 mmol L-1 tetraborate buffer at pH 9.2, and 7.5% (v/v) methanol allowed baseline resolution of all phenolic acids under investigation in less than 15 min. In order to promote sample clean up, to preconcentrate the phenolic fraction and to release esterified phenolic acids from the fruit matrix, elaborate liquid-liquid extraction procedures followed by alkaline hydrolysis were performed. The proposed methodology was fully validated (linearity from 10.0 to 100 mu g mL(-1), R-2 > 0.999: LOD and LOQ from 1.32 to 3.80 mu g mL(-1) and from 4.01 to 11.5 mu g mL(-1), respectively; intra-day precision better than 2.8% CV for migration time and 5.4% CV for peak area; inter-day precision better than 4.8% CV for migration time and 4.8-11% CV for peak area: recoveries from 81% to 115%) and applied successfully to the evaluation of phenolic contents of abiu-roxo (Chrysophyllum caimito), wild mulberry growing in Brazil (Morus nigra L.) and tree tomato (Cyphomandra betacea). Values in the range of 1.50-47.3 mu g g(-1) were found, with smaller amounts occurring as free phenolic acids. (C) 2009 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 04/08931-4 - Eletroforese capilar acoplada à espectrometria de massas como ferramenta analítica na caracterização de compostos no contexto ambiental, biotecnologia e alimentos funcionais
• Beneficiário: Marina Franco Maggi Tavares
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 07/53470-3 - Propostas metodologicas para componentes em matrizes alimenticias, alimentos enriquecidos e contaminantes utilizando eletroforese capilar acoplada a espectrometria de massas.
• Beneficiário: Tatiana Shizue Fukuji
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 04/08503-2 - Propostas metodológicas para a análise de fármacos em águas doces utilizadas no abastecimento público do estado de São Paulo
• Beneficiário: Marina Franco Maggi Tavares
• Modalidade de apoio: Auxílio à Pesquisa - Regular