A rapid and simple method for determination of 5-hydroxytryptophan in dietary supplements by capillary electrophoresis

Autor(es)

Coelho, Aline G. ^[1] ; Aguiar, Fernanda P. C. ^[1] ; de Jesus, Dosil P. ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Campinas UNICAMP, Inst Chem, BR-13083970 Campinas, SP - Brazil

^[2] Univ Campinas UNICAMP, Inst Nacl Ciencia & Tecnol Bioanalit, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. 25, n. 4, p. 783-787, APR 2014.
• Citações Web of Science: 7

Resumo

A rapid and simple capillary electrophoresis (CE) method was developed to determine 5-hydroxytryptophan (5-HTP) in samples of commercial dietary supplements. The optimized background electrolyte (BGE) was composed by 20 mmol L-1 sodium phosphate (pH 10) and 0.2 mmol L-1 cetyltrimethylammonium bromide (CTAB) for electroosmotic flow inversion. The limits of detection (LOD) and quantification (LOQ) for 5-HTP were 3.1 and 10.1 µmol L-1, respectively. The analytical curve demonstrated linearity over a concentration range of 0-500 µmol L-1 with a correlation coefficient (R²) of 0.9995. The intraday instrumental precision (repeatability) as relative standard deviation (RSD) in terms of peak area and migration time of the 5-HTP were 2.2 and 1.9% (n = 8), respectively. The CE method was applied to the analysis of four different samples of commercial dietary supplements and the RSD (n = 3) for the determinations ranged from 2 to 3%. The accuracy of the method was evaluated comparing the measured 5-HTP concentrations to those obtained by a high performance liquid chromatography (HPLC) method. The relative error ranged from 0 to 5.9% (n = 3) and no significant differences between the concentrations were observed at a confidence level of 95%. (AU)

• Processo FAPESP: 08/57805-2 - Instituto de Bioanalítica
• Beneficiário: Lauro Tatsuo Kubota
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 08/53868-0 - Síntese e caracterização de novos materiais estrategicamente estruturados e organizados para aplicações em dispositivos analíticos e fotônicos
• Beneficiário: Lauro Tatsuo Kubota
• Modalidade de apoio: Auxílio à Pesquisa - Temático