title: Validation of a selective method for determination of paroxetine in human plasma by LC-MS/MS.
abstract: OBJECTIVE
  A sensitive, robust, and selective liquid chromatographic-tandem mass spectrometric method (LC-MS/MS) was developed and validated for paroxetine quantification in human EDTA plasma.
  
  
  METHODS
  Sample preparation was based on liquid-liquid extraction using a mixture of ethyl acetate/hexane (50/50; v/v) to extract the drug and internal standard from plasma. Chromatography was performed on a C-18 analytical column and the retention times were 1.6 and 1.7 for paroxetine and fluoxetine (IS), respectively. The ionization was optimized using ESI(+) and selectivity was achieved by tandem mass spectrometric analysis using MRM functions, 330.0 --> 70.0 and 310 --> 43.9 for paroxetine and fluoxetine.
  
  
  RESULTS
  Analytical curve ranged from 0.2 to 20.0 ng/mL. Inter-day precision and accuracy of the quality control (QC) samples were < 15% relative standard deviation (RSD). Analyte stability during sampling processing and storage were established.
  
  
  CONCLUSIONS
  Validation results on linearity, specificity, accuracy, precision as well as application to the analysis of samples taken up to 120 h after oral administration of 20 mg of paroxetine in 28 healthy volunteers were found to be of good performance in bioequivalence study.
authors.affiliation: São Francisco University Medical School, Av. São Francisco de Assis 218, 12916-900, Bragança Paulista, SP, Brazil.
authors.forename: P
authors.initials: P
authors.lastname: Massaroti
authors.forename: N M
authors.initials: NM
authors.lastname: Cassiano
authors.forename: L F
authors.initials: LF
authors.lastname: Duarte
authors.forename: D R
authors.initials: DR
authors.lastname: Campos
authors.forename: M A M
authors.initials: MA
authors.lastname: Marchioretto
authors.forename: G
authors.initials: G
authors.lastname: Bernasconi
authors.forename: S
authors.initials: S
authors.lastname: Calafatti
authors.forename: F A P
authors.initials: FA
authors.lastname: Barros
authors.forename: E C
authors.initials: EC
authors.lastname: Meurer
authors.forename: J
authors.initials: J
authors.lastname: Pedrazzoli
mesh_terms: D000293:Adolescent; D000328:Adult; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods; D018592:Cross-Over Studies; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D017374:Paroxetine / Q000097:blood* / Q000737:chemistry
chemical_list: D017374:Paroxetine