Determination of L-753,037 in human plasma by liquid chromatography/turbo ionspray tandem mass spectrometry

✍ Scribed by Zhao, Jamie J.; Xie, Iris; Rogers, J. Douglas

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 124 KB
• Volume: 34
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/(sici)1096-9888(199910)34:10<1018::aid-jms860>3.0.co;2-l

✦ Synopsis

A liquid chromatographyic/turbo ionspray tandem mass spectrometric (LC/MS/MS) method was developed and validated for the determination of L-753,037, a potent endothelin receptor antagonist currently under development for the treatment of cardiovascular diseases, in human plasma. L-753,037 is extracted from 0.5 ml of human plasma using liquid-liquid extraction and analyzed by LC/MS/MS with a turbo ionspray interface. Method validation results showed that this method is very sensitive, reliable, selective and reproducible. L-753,048, an ethoxy analogue of L-753,037, was used as the internal standard. The method has a lower limit of quantitation (LOQ) of 50 pg ml -1 with a linear calibration range of 0.05-50 ng ml -1 . The intra-day precision and accuracy (n = 5) were measured to be below 10% relative standard deviation (RSD) and between 97.4 and 102.8% of the nominal values, respectively, for all calibration standard concentrations within the calibration curve range. The inter-day precision and accuracy (n = 3 days, 5 replicates per day) were measured to be below 6.5% RSD and between 99.3 and 102.0% of the nominal values, respectively, for all quality control concentrations. The extraction recovery was determined to be ∼99% on average. The analyte was found to be stable in plasma through three freeze-thaw cycles, for at least 4 h at ambient temperature and for up to 40 days under -20 • C freezer storage conditions. The analyte was also shown to be stable for at least 24 h in the reconstitution solution at room temperature and for up to 3 days as a dried extract at 4 • C. Additional variations in plasma concentration of the analyte due to the use of different sources of plasma were also evaluated.