Abstract
Sensitive and specific liquid-chromatography tandem mass spectrometry (UPLC-MS/MS) assay has been developed and validated for simultaneous quantification of risperidone (RIS) and its active metabolite 9-hydroxyrisperidone (9-OH-RIS) in rat plasma using olanzapine (OLA) as internal standard (IS). Pharmacokinetics of risperidone and its active metabolite 9-hydroxyrisperidone was compared across different doses (0.3, 1.0, and 6.0 mg/kg). Serial blood sample was collected over a time of 48 hours and analyzed for risperidone and its active metabolite 9-hydroxyrisperidone. The pharmacokinetics parameters including
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, and AUC were determined for risperidone and its active ingredient. The method was linear in the concentration range of 0.2–500 ng/mL for risperidone and 9-OH-risperidone, with coefficients of determination greater than 0.998 and lower limit of quantitation of 0.2 ng/mL. Blood levels of risperidone and its active metabolite were roughly dose-proportional. The method developed herein is simple and rapid and was successfully applied for dose-dependent pharmacokinetic study.