Simultaneous quantification of the enantiomers of verapamil and its N-demethylated metabolite in human plasma using liquid chromatography–tandem mass spectrometry

An LC‐MS/MS method for simultaneous determination of vincristine and verapamil in rat plasma after oral administration of a dual agent formulation

“…The methods used for verapamil quantification in plasma samples include GC (Hege, 1979), GC/MS (Hynning et al, 1988), HPLC with fluorescence (Sawicki, 2001;Jhee et al, 2005) or ultraviolet detection (Lau-Cam and Piemontese, 1998;Ivanova et al, 2008) and liquid chromatographic-mass spectrometric methods (Von Richter et al, 2000;Hedeland et al, 2004). All of the above methods require a large volume (at least 500 mL) of plasma sample.…”

Recent studies on the electrospray ionisation mass spectrometric behaviour of selected nitrogen-containing drug molecules and its application to drug analysis using liquid chromatography–electrospray ionisation mass spectrometry

“…The other main metabolites are D617, D620 and PR23. A stereoselective LC-ESI-MS/MS method for the simultaneous quantification of the enantiomers of verapamil and its active main metabolite norverapamil in human plasma has been developed and validated by Hedeland et al [24]. Structures of these molecules and suggested fragmentations are given in Fig.…”

HPLC method for determination of verapamil in human plasma after solid-phase extraction

“…Some of them employ fluorescence detection [3][4][5][6][7][8][9][10], very few employ spectrophotometric detection in the UV range [11,12], whereas mass spectrometric detection is used in the recent developed methods [13][14][15][16][17].…”

“…As for the sample preparation procedures employed prior to the HPLC determination of verapamil, there is a diversity in the speed and complexity of the clean-up methods starting from direct determination of verapamil from rat plasma [7], through using only deproteinization of the plasma samples [11,13] to the more complex ones such as liquid-liquid extraction (LLE) using various organic solvents [3,4,6,9,10,15] and solid-phase extraction (SPE) with various adsorbents [4,8,9,17]. The most sophisticated sample preparation procedures employ automated column switching techniques for on-line sample preparation [5,7,8,12].…”