Development and validation of a UPLC-ESI-MS/MS method for the determination of N-butylscopolamine in human plasma: Application to a bioequivalence study

Abstract

A sensitive and fast ultra performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method for measurements of N-butylscopolamine in plasma was developed and validated. A single protein precipitation was proposed for the clean up of the plasma and N-methylhomatropine was added as internal standard (IS). The analyses were carried out using a C18 column and mobile phase of acetonitrile: 5mM ammonium acetate+0.1% formic acid (90:10, v/v). The triple quadrupole mass spectrometer equipped with an electrospray source in positive mode, was set up in selective reaction monitoring, to detect precursor→product ion 360.0→194.0m/z and 290.3→138.0m/z transitions, for N-butylscopolamine and IS, respectively. The method was linear in 0.03 (lower limit of quantitation; LLOQ) - 10.00ng/ml range for N-butylscopolamine. Satisfactory selectivity, linearity, precision, accuracy, and robustness were obtained for the UPLC-ESI-MS/MS method. The proposed method was successfully applied to a pharmacokinetic study of healthy human volunteers; the results showed that the two scopolamine butylbromide formulations tested are not bioequivalent in rate and extent of absorption. Copyright © 2012 John Wiley & Sons, Ltd. A sensitive and fast UPLC-ESI-MS/MS method for measurements of N-butylscopolamine in plasma was developed and validated using protein precipitation for the clean up of the plasma and N-methylhomatropine with internal standard (IS). The acquisition was performed in the multiple reaction monitoring mode monitoring the transitions: m/z 360.0 → 194.0 for N-butylscopolamine and m/z 290.3 → 138.0 for SI with positive ion electrospray ionization using a mobile phase of acetonitrile: 5mM ammonium acetate + 0.1% formic acid (90:10, v/v). The method was linear in 0.03 (lower limit of quantitation; LLOQ) - 10.00 ng/mL and demonstrated to be selectivity, linearity, precision, accuracy, robustness and was successfully applied to a pharmacokinetic study of healthy human volunteers; the results showed that the two scopolamine butylbromide formulations tested are not bioequivalent in rate and extent of absorption. © 2012 John Wiley & Sons, Ltd.