Verapamil quantification in human plasma by liquid chromatography coupled to tandem mass spectrometry An application for bioequivalence study

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Analytical technologies in the biomedical and life sciences, 2005-12, Vol.827 (2), p.165-172
• Main Authors: BORGES, Ney Carter Do C, MENDES, Gustavo D, BARRIENTOS-ASTIGARRAGA, Rafael E, GALVINAS, Paulo, OLIVEIRA, Celso H, DE NUCCI, Gilberto
• Format: Article
• Language: English
• Subjects: Analysis; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Chromatography, Liquid - methods; Drug Stability; Fundamental and applied biological sciences. Psychology; General pharmacology; Humans; Medical sciences; Pharmacology. Drug treatments; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization - methods; Therapeutic Equivalency; Verapamil - blood; Verapamil - pharmacokinetics
• ISSN: 1570-0232; 1873-376X
• DOI: 10.1016/j.jchromb.2005.07.012

An analytical method based on liquid chromatography with positive ion electrospray ionization (ESI) coupled to tandem mass spectrometry detection (LC-MS/MS) was developed for the determination of Verapamil in human plasma using Metoprolol as the internal standard. The analyte and internal standard were extracted from the plasma samples by liquid-liquid extraction and chromatographed on a C(8) analytical column. The mobile phase consisted of methanol-water (70:30; v/v)+12 mM formic acid. The method had a chromatographic total run time of 3.5 min and was linear within the range 1.00-500 ng/mL. Detection was carried out on a Micromass Quattro Ultima tandem mass spectrometer by multiple reaction monitoring (MRM). The intra-run imprecision was less than 5.1% calculated from the quality control (QC) samples, and 16.3% from the limit of quantification (LOQ). The accuracy determined from QC samples were between 92.9 and 103.1%, and 95.2 and 115.3% from LOQ. Concerning the inter-batch analysis, the imprecision was less than 5.8% and 17.3% from QC samples and LOQ, respectively. The accuracy varied between 98.2 and 100.8% from QC and it was 103.1% from LOQ. The protocol herein described was employed in a bioequivalence study of two tablet formulations of Verapamil.