RESUMEN
A simple, rapid, sensitive and specific LC-MS/MS method was developed and validated for the quantitative determination of doxylamine in human plasma, using isotope doxylamine-d5 as internal standard (IS). The detection was conducted on a QTRAP 5500 tandem mass spectrometer coupled with electrospray ionization (ESI) source in positive ion mode. Quantification was achieved by positive electrospray ionization containing multiple reaction monitoring (MRM) transitions of m/z 271.0â182.0 for doxylamine and m/z 276.2â187.3 for IS. The mobile phase A was methanol, and mobile phase B was 20 mM ammonium acetate (0.2 % formic acid) in water, using a gradient elution procedure at a flow rate of 0.6 mL/min. The method was validated with a sensitivity of 0.500 ng/mL and a linear concentration range of 0.500-200 ng/mL. The inter-batch precision (%CV) was less than 5.4 %, and the accuracy deviation (%RE) ranged from - 10.6 % to 3.7 %; the inter-batch precision (%CV) was less than 6.6 %, and the accuracy deviation (%RE) was ranged from - 2.7 % to 0.1 %. The selectivity, sensitivity, extraction recovery, matrix effect, carryover, dilution reliability, stability and other characteristics were within the acceptable range. This validated method was successfully applied to a bioequivalence study that orally administered 25 mg of doxylamine succinate tablets in 60 healthy Chinese volunteers.
Asunto(s)
Doxilamina/sangre , Doxilamina/farmacocinética , Antagonistas de los Receptores Histamínicos H1/sangre , Antagonistas de los Receptores Histamínicos H1/farmacocinética , Espectrometría de Masas en Tándem/métodos , Administración Oral , China , Cromatografía Liquida/métodos , Doxilamina/administración & dosificación , Voluntarios Sanos , Antagonistas de los Receptores Histamínicos H1/administración & dosificación , Humanos , Metanol , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray , Comprimidos , Equivalencia TerapéuticaRESUMEN
A rapid, simple, and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was validated for the determination of terbinafine concentrations in the plasma of healthy Chinese subjects. Terbinafine-d7 was used as the internal standard (IS), and the acetonitrile protein precipitation method was selected. The processed samples were chromatographically separated with a C18 column. The mobile phases were 0.1% formic acid (FA) in water (A), and methanol (B), respectively, and the gradient elution program was used with a flow rate of 0.8 mL/min. Quantification was achieved by positive electrospray ionization containing multiple reaction monitoring (MRM) transitions of m/z 292.5 â 141.1 for terbinafine and m/z 299.5 â 148.1 for IS. The calibration curve range was 2.00-1200 ng/mL; the intra- and inter-batch precision (coefficient of variation, %CV) was <8.2%, with the accuracy deviation (relative error, %RE) of -6.5% to 10.2%. The selectivity, sensitivity, extraction recovery, matrix effect, dilution reliability, carryover, and stability were within the acceptable range. This method was successfully applied to a bioequivalence study that orally administered 125 mg of terbinafine hydrochloride tablets in 84 healthy Chinese subjects.