Liquid chromatography-mass spectrometry assay for quantitation of ifosfamide and its N-deschloroethylated metabolites in rat microsomal medium.
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.
Storme
Thomas
T
Department of Clinical Pharmacy, Institute Gustave Roussy, Villejuif, France.
Mercier
Lionel
L
Deroussent
Alain
A
Re
Micheline
M
Martens
Thierry
T
Royer
Jacques
J
Bourget
Philippe
P
Vassal
Gilles
G
Paci
Angelo
A
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*
D018906:Antineoplastic Agents, Alkylating; D003470:Culture Media; D007069:Ifosfamide