title: High-performance liquid chromatographic determination of naproxen, ibuprofen and diclofenac in plasma and synovial fluid in man.
abstract: High-performance liquid chromatographic assay procedures have been developed for naproxen, ibuprofen and diclofenac in human plasma and synovial fluid samples. A single liquid-liquid extraction procedure was used to isolate each compound from acidified biological matrix prior to the quantitative analysis. A Spherisorb ODS column (12.5 cm x 4.6 mm I.D.) was used for all the chromatography. Naproxen was eluted with a mobile phase of methanol-Sörensen's buffer at pH 7 (37:63, v/v). Ibuprofen and diclofenac were eluted using mobile phases of methanol-water at pH 3.3 (65:35, v/v and 63:37, v/v, respectively). Diphenylacetic acid was used as the internal standard for the assay of naproxen and flurbiprofen was used in the analysis of ibuprofen and diclofenac. Inter- and intra-day coefficients of variation were less than 7%. The assays were used in clinical studies of the three drugs in osteo- and rheumatoid arthritis patients.
authors.affiliation: Department of Pharmaceutical Sciences, University of Nottingham, University Park, UK.
authors.forename: I S
authors.initials: IS
authors.lastname: Blagbrough
authors.forename: M M
authors.initials: MM
authors.lastname: Daykin
authors.forename: M
authors.initials: M
authors.lastname: Doherty
authors.forename: M
authors.initials: M
authors.lastname: Pattrick
authors.forename: P N
authors.initials: PN
authors.lastname: Shaw
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004008:Diclofenac / Q000097:blood / Q000378:metabolism*; D006801:Humans; D007052:Ibuprofen / Q000097:blood / Q000378:metabolism*; D009288:Naproxen / Q000097:blood / Q000378:metabolism*; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet; D013582:Synovial Fluid / Q000737:chemistry*
chemical_list: D004008:Diclofenac; D009288:Naproxen; D007052:Ibuprofen