title: Chromatographic separation and sensitive determination of teriflunomide, an active metabolite of leflunomide in human plasma by liquid chromatography-tandem mass spectrometry.
abstract: A sensitive, selective and high throughput liquid chromatography tandem mass spectrometry (LC-ESI-MS/MS) method has been developed for the determination of teriflunomide, an active metabolite of leflunomide in human plasma. Plasma samples were prepared by liquid-liquid extraction of teriflunomide and valsartan as internal standard (IS) in ethyl acetate from 200microL human plasma. The chromatographic separation was achieved on an Inertsil ODS-3 C18 (50mmx4.6mm, 3microm) analytical column using isocratic mobile phase, consisting of 20mM ammonium acetate-methanol (25:75, v/v), at a flow-rate of 0.8mL/min. The precursor-->product ion transition for teriflunomide (m/z 269.0-->82.0) and IS (m/z 434.1-->350.3) were monitored on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring (MRM) and negative ion mode. The method was validated over a wide dynamic concentration range of 10.1-4001ng/mL. Matrix effect was assessed by post-column infusion experiment and the mean process efficiency were 91.7% and 88.2% for teriflunomide and IS respectively. The method was rugged and rapid with a total run time of 2.0min and is applied to a bioequivalence study of 20mg leflunomide (test and reference) tablet formulation in 12 healthy Indian male subjects under fasting condition.
authors.affiliation: Chemistry Department, School of Sciences, Gujarat University, Navrangpura, Ahmedabad 380009, India.
authors.forename: Jignesh M
authors.initials: JM
authors.lastname: Parekh
authors.forename: Rajendrasinh N
authors.initials: RN
authors.lastname: Vaghela
authors.forename: Dipen K
authors.initials: DK
authors.lastname: Sutariya
authors.forename: Mallika
authors.initials: M
authors.lastname: Sanyal
authors.forename: Manish
authors.initials: M
authors.lastname: Yadav
authors.forename: Pranav S
authors.initials: PS
authors.lastname: Shrivastav
mesh_terms: D000085:Acetates; D000328:Adult; D002853:Chromatography, Liquid / Q000379:methods*; D003437:Crotonates / Q000097:blood* / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics*; D004355:Drug Stability; D057166:High-Throughput Screening Assays / Q000379:methods; D006801:Humans; D006885:Hydroxybutyrates; D007555:Isoxazoles / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics*; D016018:Least-Squares Analysis; D000077339:Leflunomide; D008297:Male; D008875:Middle Aged; D009570:Nitriles; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013810:Therapeutic Equivalency; D014052:Toluidines / Q000097:blood* / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics*
chemical_list: D000085:Acetates; D003437:Crotonates; D006885:Hydroxybutyrates; D007555:Isoxazoles; D009570:Nitriles; D014052:Toluidines; C527525:teriflunomide; C007650:ethyl acetate; D000077339:Leflunomide