Improved enantioselective assay for the determination of fluoxetine and norfluoxetine enantiomers in human plasma by liquid chromatography

Enantioselective analysis of fluoxetine and norfluoxetine in plasma samples by protein precipitation and liquid chromatography with fluorescence detection

“…The PP/LC-FD method developed here give values of accuracy and linearity close to those achieved with sample preparation methods previously described in the literature, such as liquid-liquid extraction (LLE/LC-UV), 1 solid phase extraction (SPE/LC -FD), 4 and LLE/GC-NPSD (nitrogen-phosphorus selective detector), 23 for analysis of these enantiomers in biological matrices.…”

“…1 The mobile phase consisted of potassium hexafluorophosphate 7.5 mmol L -1 and sodium phosphate 0.25 mol L -1 solution, pH 3, acetonitrile (75:25, v/v), at a flow rate of 1.0 mL min −1 in the isocratic mode. Under this set conditions, the LC-FD analysis in the selected mobile phase furnished appropriate resolution and satisfactory analysis time (23 min).…”

“…The lack of a suitable test to discriminate between the R and S enantiomers of fluoxetine and its active demethylated metabolite, norfluoxetine (NFLX), has hampered assessments of the potential correlation between clinical response and plasma levels of fluoxetine and / or norfluoxetine for many years. 1 The chemical structures of the enantiomers of fluoxetine and norfluoxetine are shown in Figure 1.…”

Comparison of the performance of chiral stationary phase for separation of fluoxetine enantiomers

“…HPLC using chiral stationary phases (CSPs) is more effective (Gatti et al, 2003;Kaddoumi et al, 2001;Olsen et al, 1998;Wang and Yun, 1997;Bakhtiar and Tse, 2000;Shen et al, 2002;Yee et al, 2000;Piperaki and Poulou, 1993;Berthod et al, 1990;Yu et al, 2002). By using tris (3,5-dimethylphenyl carbamate) cellulose (chiralcel OD-H), Gatti et al(2003) obtained a separation factor (α) of 1.10. Olsen et al(1998) (Piperaki and Poulou, 1993;Berthod et al, 1990).…”

Influência da exposição inalatória a combustíveis automotivos na atividade do CYP3A, CPY2C e CYP2D em ratos tratados com fármacos quirais

“…Outros métodos empregando eletroforese capilar também são descritos (JABOR et al;2002;GLÓWKA;KARAZNIEWICZ;2007 A análise dos enantiômeros da fluoxetina em plasma tem sido descrita por HPLC com detecção por ultravioleta, florescência ou por espectrometria de massas (MS/MS) empregando procedimentos de derivatização (GUO et al, 2003;YU et al, 2006) ou colunas com fases estacionárias quirais (OLSEN et al, 1998;TSE, 2000;GATTI et al, 2003;JIE et al, 2007;CHOW et al, 2011). Nos estudos de precisão intra e inter-ensaios, os coeficientes de variação obtidos são iguais ou inferiores a 15% o que indica a alta precisão do método analítico.…”