title: Determination of (S)-(+)- and (R)-(-)-ibuprofen enantiomers in human plasma after chiral precolumn derivatization by reversed-phase LC-ESI-MS/MS.
abstract: BACKGROUND
  A selective, sensitive and high-throughput LC-ESI-MS/MS method has been developed and validated for the chromatographic separation and quantitation of (S)-(+)-ibuprofen and (R)-(-)-ibuprofen after derivatization with (S)-(-)-1-(1-napthyl)ethylamine using 1-hydroxybenzotriazole as the activator of the carboxylic acid group and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide as the coupling reagent in human plasma.
  
  
  RESULTS
  Both the analytes were chromatographically separated with a resolution factor of 1.27 on a Kinetex PFP (50 × 4.6 mm, 2.6 µm) analytical column. The method was validated over the concentration range of 0.10-32.0 µg/ml for both the enantiomers. The magnitude of matrix effect was assessed by post-column analyte infusion and also by precision (%CV) values for the calculated slopes of calibration curves. The mean extraction recovery was >91% for both the enantiomers.
  
  
  CONCLUSIONS
  The method was successfully applied to a bioequivalence study in 34 healthy human subjects. The assay reproducibility was confirmed by reanalysis of 130 subject samples.
authors.affiliation: Department of Chemistry, School of Sciences, Gujarat University, Ahmedabad 380009, India.
authors.forename: Primal
authors.initials: P
authors.lastname: Sharma
authors.forename: Swati
authors.initials: S
authors.lastname: Guttikar
authors.forename: Gajendra
authors.initials: G
authors.lastname: Solanki
authors.forename: Daxesh P
authors.initials: DP
authors.lastname: Patel
authors.forename: Pranav S
authors.initials: PS
authors.lastname: Shrivastav
mesh_terms: D000293:Adolescent; D000328:Adult; D002845:Chromatography; D002853:Chromatography, Liquid / Q000379:methods; D018592:Cross-Over Studies; D006801:Humans; D007052:Ibuprofen / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D013237:Stereoisomerism; D013607:Tablets; D053719:Tandem Mass Spectrometry / Q000379:methods; D013810:Therapeutic Equivalency; D055815:Young Adult
chemical_list: D013607:Tablets; D007052:Ibuprofen