title: Determination of fluoxetine and norfluoxetine in rat plasma by HPLC with pre-column derivatization and fluorescence detection.
abstract: Both fluoxetine (FLX) and its N-demethylated metabolite, norfluoxetine (NFLX), have been reported to be potent serotonin-reuptake inhibitors. A sensitive and reliable method that allows simultaneous quantification of their plasma levels would be valuable and was developed in this work. The procedure included extraction of FLX and NFLX from plasma, fluorescence derivatization with 4-(N-chloroformylmethyl-N-methyl) amino-7-nitro-2,1,3-benzoxadiazole (NBD-COCl), separation of the derivatives on an octadecylsilica column with acetonitrile-water (55:45,v/v) as mobile phase and fluorescence detection with emission at 537 nm and excitation at 478 nm. The calibration curves were linear for FLX and NFLX concentration over the range of 10-1000 nM (r = 0.9992 and r = 0.9997) and the limits of quantitation were 10 nM in 100 micro L of plasma. Precision of intra- and inter-day RSD of less than 12% and accuracy of intra- and inter-day RE within -6.0-13% were achieved. The method described was applied to analysis of the plasma samples from rats treated with FLX hydrochloride and to the pharmacokinetic study.
authors.affiliation: Laboratory of Bio-Analytical Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. gxjhyz@yahoo.com.cn
authors.forename: Xingjie
authors.initials: X
authors.lastname: Guo
authors.forename: Takeshi
authors.initials: T
authors.lastname: Fukushima
authors.forename: Famei
authors.initials: F
authors.lastname: Li
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Imai
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005473:Fluoxetine / Q000031:analogs & derivatives* / Q000097:blood*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017367:Selective Serotonin Reuptake Inhibitors / Q000097:blood*; D013050:Spectrometry, Fluorescence
chemical_list: D005473:Fluoxetine; D017367:Selective Serotonin Reuptake Inhibitors; C036139:norfluoxetine