title: Identification of degradation products of diclofenac by electrospray ion trap mass spectrometry.
abstract: The degradation products of diclofenac in aqueous dosage form in accelerated storage conditions were characterized by electrospray ionization-ion trap mass spectrometry (ESI-MS). Liquid chromatography (LC)-MS analyses revealed the presence of three degradation products. ESI-MS(n) spectra were used to study diclofenac fragmentation in detail and to characterize the structures of degradation products. A previously described degradation product, formed by a cyclization reaction of diclofenac producing the indolinone derivative, was found. As any hydroxylated product was found, no oxidation seems to occur in the dosage form used. On the contrary, two degradates have been detected and identified, leading to a primary alcohol structure or an aldehyde function in place of the acetate group of diclofenac.
authors.affiliation: Laboratoire de Chimie Analytique et de Spectrométrie de Masse, UFR de Pharmacie, Place Henri Dunant, B.P. 38, F- 63001 Clermont-Ferrand Cedex, France. galmier@inserm484.u-clermont1.fr
authors.forename: Marie-Josèphe
authors.initials: MJ
authors.lastname: Galmier
authors.forename: Bernadette
authors.initials: B
authors.lastname: Bouchon
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Madelmont
authors.forename: Fabrice
authors.initials: F
authors.lastname: Mercier
authors.forename: Frédéric
authors.initials: F
authors.lastname: Pilotaz
authors.forename: Claire
authors.initials: C
authors.lastname: Lartigue
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004008:Diclofenac / Q000032:analysis*; D004355:Drug Stability; D008401:Gas Chromatography-Mass Spectrometry; D007202:Indicators and Reagents; D012996:Solutions; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D014867:Water
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007202:Indicators and Reagents; D012996:Solutions; D014867:Water; D004008:Diclofenac