Development and validation of a LC-MS assay for the quantification of ikh12 a novel anti-tumor candidate in rat plasma and tissues and its application in a pharmacokinetic study.

IKH12 is a novel histone deacetylase 6 selective inhibitor. A rapid and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of IKH12 in rat plasma and tissue with kendine 91 as internal standard (IS). The samples were prepared by liquid-liquid extraction with tert-butyl methyl ether. The chromatographic separation was accomplished by using a Zorbax Extend C-18 4.6x150mm, 5 mu m column, with a mobile phase consisting of methanol and 0.1% formic acid (75:25v/v). Multiple reaction monitoring, using electrospray ionization in positive ion mode, was employed to quantitatively detect IKH12 and IS. The monitored transitions were set at m/z 418252 and 444169 for IKH12 and kendine 91, respectively. The calibration curve was linear over the concentration range 2-1000ngmL(-1). The intra- and inter-assay precision and accuracy of the quality controls and the limit of quantification were satisfactory in all cases (according to European Medicines Agency guidelines). Stability studies showed that plasma samples were stable in the chromatography rack for 24h and at -80 degrees C for 2months and also after three freeze-thaw cycles. This method was successfully applied to a pharmacokinetic study of IKH12 in rat. Copyright (c) 2015 John Wiley & Sons, Ltd.