Sensitive HPLC method for the determination of fluoxetine and norfluoxetine in human plasma with fluorescence detection
THERAPEUTIC DRUG MONITORING, vol.27, no.1, pp.38-43, 2005 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 27 Issue: 1
- Publication Date: 2005
- Doi Number: 10.1097/00007691-200502000-00009
- Journal Name: THERAPEUTIC DRUG MONITORING
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Page Numbers: pp.38-43
- Istanbul University Affiliated: Yes
Abstract
A selective, sensitive, and precise HPLC method for the simultaneous determination of fluoxetine (FL) and its N-demethylated metabolite norfluoxetine (NFL) in human plasma has been developed. Following extraction with n-hexane, FL, NFL, and fluvoxamine (internal standard) were derivatized with 7-chloro-4-nitrobenzofurazan (NBD-Cl) under weakly alkaline conditions. NBD derivatives were extracted with chloroform after acidification and chromatographed on a reversed-pbase column with gradient elution using acetonitrile and 0.1 mol/L nitric acid (pH 3) solution. Calibration curves were linear over the range of 1.0-100.0 ng/mL and 0.1-50.0 ng/mL for FL and NFL, respectively, with inter- and intraassay precision given by a relative standard deviation (RSD%) of less than 9.2%. The lower limits of quantification were 1.0 ng/mL for FL and 0.1 ng/mL for NFL. Recoveries of FL and NFL from plasma at three different concentrations were assessed. Average recovery was about 100% for both substances. The assay was applied to pharmacokinetic study in 2 healthy volunteers after a single oral administration of 40 mg of FL.