title: Liquid chromatography-mass spectrometry assay for quantitation of ifosfamide and its N-deschloroethylated metabolites in rat microsomal medium.
abstract: A specific and sensitive quantitative assay has been developed using high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS) for the simultaneous quantitation of the antitumor drug ifosfamide (IFM) and its two metabolites, N2-deschloroethylifosfamide (N2-DCE-IFM) and N3-deschloroethylifosfamide (N3-DCE-IFM) in microsomal medium. The analytes and the internal standard (cyclophosphamide) were isolated by ethylacetate extraction from rat liver microsomes. They were analysed on a Nucleosil C18 HD column (125 mm x 4 mm, 5 microm) using a step gradient with the mobile phase (2 mM ammonium formate and methanol). The HPLC-ESI-MS method used selected ion monitoring of ions m/z 199.1 Th and m/z 261.1 Th and was validated in the concentrations ranges of 100-5000 ng/mL for IFM and 50-2500 ng/mL for its N-deschloroethylated metabolites (DCE-IFM) with good accuracy and precision (CV less than 15%). The low limits of quantitation (LLOQ) were found at 50 ng/mL for N-deschloroethylated metabolites and at 100 ng/mL for the parent drug (IFM). The method was applied for the determination of ifosfamide and its N-deschloroethylated metabolites in rat microsomal incubations.
authors.affiliation: Department of Clinical Pharmacy, Institute Gustave Roussy, Villejuif, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Storme
authors.forename: Lionel
authors.initials: L
authors.lastname: Mercier
authors.forename: Alain
authors.initials: A
authors.lastname: Deroussent
authors.forename: Micheline
authors.initials: M
authors.lastname: Re
authors.forename: Thierry
authors.initials: T
authors.lastname: Martens
authors.forename: Jacques
authors.initials: J
authors.lastname: Royer
authors.forename: Philippe
authors.initials: P
authors.lastname: Bourget
authors.forename: Gilles
authors.initials: G
authors.lastname: Vassal
authors.forename: Angelo
authors.initials: A
authors.lastname: Paci
mesh_terms: D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003470:Culture Media; D007069:Ifosfamide / Q000032:analysis*; D008862:Microsomes, Liver / Q000737:chemistry*; D051381:Rats; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D018906:Antineoplastic Agents, Alkylating; D003470:Culture Media; D007069:Ifosfamide