Determination of Urapidil Hydrochloride in Rabbit Plasma by Lc-MS-MS and Its Application to a Pharmacokinetic Study

Abstract

A sensitive and selective liquid chromatography tandem mass spectrometry (LC-MS-MS) method for determination of urapidil hydrochloride in rabbit plasma was developed and validated. After addition of doxapram hydrochloride as the internal standard (IS), protein precipitation by 10% trichloroacetic acid was used as the sample preparation. Chromatographic separation was achieved on a Zorbax SB-C18 (2.1 mm  50 mm, 3.5 lm) column with acetonitrile-water as the mobile phase with gradient elution. Electrospray ionization (ESI) source was applied and operated in positive ion mode; multiple reaction monitoring (MRM) mode was used to quantification using target fragment ions m=z 387.9 ! 204.6 for urapidil hydrochloride and m=z 378.9 ! 291.8 for the IS. Calibration plots were linear over the range of 5-1000 ng=mL for urapidil hydrochloride in plasma. Lower limit of quantitation (LLOQ) for urapidil hydrochloride was 5 ng=mL. Mean recovery of urapidil hydrochloride from plasma was in the range 93.5%-96.4%. RSD of intra-day and inter-day precision were both less than 12%. This developed method is successfully used in pharmacokinetic study of urapidil hydrochloride in rabbit.

3D Graphene-Nitrogen Doped Carbon Nanotubes Network Modified Electrode as Sensing Materials for the Determination of Urapidil

“…UV-vis and flow-injection chemiluminescence [ 3 , 4 ] was first employed, but it suffered from low detection limit and narrow linear range. Recently, several analytical methods, such as high performance liquid chromatography (HPLC) [ 5 ], liquid chromatography-mass spectrometry (LC-MS) [ 6 , 7 ], capillary electrophoresis (CE) [ 8 ], and atomic absorption spectrometery (AAS) [ 9 ], have been also proposed for determination of urapidil. Although these methods have some advantages of accuracy and sensitivity, they require tedious pretreatment procedures, or complicated pre-separation processes, at high cost.…”