A liquid chromatography/tandem mass spectrometry method for determination of obatoclax in human plasma.

Abstract

We describe a selective and highly sensitive high-performance liquid chromatography-electrospray ionization-collision induced dissociation-tandem mass spectrometry (HPLC-ESI-CID-MS/MS) assay for the pan-antiapoptotic Bcl-2 family inhibitor, obatoclax, in human plasma. Fifty μL plasma specimens were prepared by addition of extraction solution consisting of Mobile Phase A (10mM ammonium formate (aq) titrated to pH of 3.0 with formic acid): Mobile Phase B (100% methanol) (20:80, v,v) and internal standard followed by centrifugation. HPLC separations were performed on a Waters, YMC-Pack™, ODS-AQ™ S-3 analytical column with LC mobile phase A and B. Linearity and sensitivity was assessed over a linear range of 0.04-25ng/ml at eleven concentrations. The lower limit of quantification for obatoclax was 0.04ng/mL. The intra-day precision based on the standard deviation of replicates of quality control (QC) samples ranged from 0.9 to 5.1% and the accuracy ranged from 98.9 to 106.8%. Stability studies performed replicate sets of QC samples (0.1ng/mL, 2.5ng/mL, and 15ng/mL) showed that obatoclax in human plasma was stable at room temperature for 24h as well as at -80°C for 1m and 2y. Stability was also demonstrated after 3 freeze/thaw cycles (RT to -80°C). The analytical method showed excellent sensitivity, precision, and accuracy. This method is robust and has been successfully employed in a Children's Oncology Group Phase 1 Consortium study of obatoclax in children with cancer.

• Authors: Ganesh S Moorthy, Robin E Norris, Peter C Adamson, Elizabeth Fox
• Journal: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences (J Chromatogr B Analyt Technol Biomed Life Sci) Vol. 971 Pg. 30-4 (Nov 15 2014) ISSN: 1873-376X [Electronic] Netherlands
• PMID: 25261914 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2014 Elsevier B.V. All rights reserved.

Chemical References

• Indoles
• Proto-Oncogene Proteins c-bcl-2
• Pyrroles
• obatoclax

Topics

• Apoptosis
• Chromatography, High Pressure Liquid (methods)
• Drug Stability
• Humans
• Indoles
• Proto-Oncogene Proteins c-bcl-2 (antagonists & inhibitors)
• Pyrroles (blood)
• Quality Control
• Reproducibility of Results
• Sensitivity and Specificity
• Spectrometry, Mass, Electrospray Ionization (methods)
• Tandem Mass Spectrometry (methods)