Sensitive triple-quadrupole mass spectrometric assay for the determinationof BMS-181885, a 5-HT1 agonist, in human plasma following solid phase extraction

A sensitive, selective, accurate, precise and reproducible triple-quadrupol e liquid chromatographic-mass spectrometric assay was developed and validat ed for BMS-181885 (I), a 5HT1 agonist, in human plasma using BMS-181101 as the internal standard (IS). The method involved solid phase extraction of p lasma containing I and the IS using Isoelute CN cartridges. The supernatant was then evaporated to dryness at 40 degrees C. The residue was dissolved in 100 mu L Of the injecting solvent. The HPLC ccolumn was ODS-3, 2 x 100 m m. The mobile phase comprised 10 mM ammonium formate (pH = 4) and acetonitr ile, 55:45 v/v, used in an isocratic condition. The mass spectrometer was p rogrammed to admit the protonated molecules at m/z 461 (I) and m/z 370 (IS) via the first quadrupole filter and to select reaction monitoring of ions at m/z 152 for I and IS for the quantification. Standard curves were fitted to a weighted quadratic function over the concentration range 0.2-200 ng/m L. The lowest standard concentration (0.2 ng/mL) was experimentally establi shed as the lower limit of quantitation of the assay. The mean predicted qu ality control concentrations deviated within +/- 11% of the corresponding n ominal values; the intra-assay and inter-assay precisions were within 7.0% relative standard deviation. I was stable in the injection solvent at 4 deg rees C for at least 24 h and for at least three freeze-thaw cycles. Freezer stability of I in plasma was demonstrated for at least 3 months. The extra ction recovery of I was established as 97%. The validated assay was applied to a pharmacokinetic study of I in humans. Copyright (C) 1999 John Wiley & Sons, Ltd.