title: Simple, sensitive and rapid determination of linifanib (ABT-869), a novel tyrosine kinase inhibitor in rat plasma by UHPLC-MS/MS.
abstract: BACKGROUND
  Linifanib (ABT-869) is an orally active receptor tyrosine kinase inhibitor, which simultaneously inhibits vascular endothelial and platelet derived growth factor receptor. The aim of the present study was to develop an UHPLC-MS/MS method for the quantification of linifanib in rat plasma to support the pharmacokinetic and toxicokinetic studies.
  
  
  RESULTS
  Linifanib was separated on Acquity UPLC BEH™ C18 column (50 × 2.1 mm, i.d. 1.7 μm) using acetonitrile-10 mM ammonium acetate (60:40, v/v) as an isocratic mobile phase at a flow rate of 0.3 mL/min with sunitinib as internal standard (IS). Detection was performed on tandem mass spectrometer using electrospray ionization source in positive mode by multiple reaction monitoring. The monitored transitions were set at m/z 376.05 > 250.97 for linifanib and m/z 399.12 >283.02 for IS, respectively. Both linifanib and IS were eluted at 0.68 and 0.44 min, respectively with a total run time of 2.0 min only. The calibration curve was found to be linear over the concentration range of 0.40-500 ng/mL. The intra- and inter-day precision value was ≤10.6% and the accuracy ranged from 90.9-108.9%. In addition, all the validation results were within general assay acceptability criteria according to guidelines of bio-analytical method validation.
  
  
  CONCLUSIONS
  A selective and sensitive UHPLC-MS/MS method was developed and validated for the determination of linifanib in rat plasma for the first time. The developed method is simple, sensitive and rapid in terms of chromatographic separation and sample preparation and was successfully applied in a pilot pharmacokinetic study in rats.
authors.affiliation: Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P,O, Box 2457, Riyadh 11451, Saudi Arabia. muziqbal@gmail.com.
authors.forename: Muzaffar
authors.initials: M
authors.lastname: Iqbal
authors.forename: Essam
authors.initials: E
authors.lastname: Ezzeldin
authors.forename: Tanveer A
authors.initials: TA
authors.lastname: Wani
authors.forename: Nasr Y
authors.initials: NY
authors.lastname: Khalil