title: A rapid and sensitive LC-MS/MS method for quantification of donepezil and its active metabolite, 6-o-desmethyl donepezil in human plasma and its pharmacokinetic application.
abstract: A rapid and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) assay method has been developed and fully validated for simultaneous quantification of donepezil and its active metabolite, 6-o-desmethyl donepezil in human plasma. Analytes and the internal standard were extracted from human plasma by liquid-liquid extraction technique using a 30:70 v/v mixture of ethyl acetate and n-hexane. The reconstituted samples were chromatographed on a C(18) column by using a 70:30 v/v mixture of acetonitrile and ammonium formate (5 mm, pH 5.0) as the mobile phase at a flow rate of 0.6 mL/min. The calibration curve obtained was linear (r ≥ 0.99) over the concentration range of 0.09-24.2 ng/mL for donepezil and 0.03-8.13 ng/mL for 6-o-desmethyl donepezil. The results of the intra-day and inter-day precision and accuracy studies were well within the acceptable limits. The proposed method was successfully applied for the estimation of the drug in real time plasma samples for pharmacokinetic studies.
authors.affiliation: University College of Pharmaceutical Sciences, Jawaharlal Nehru Technological University, Kukatpally, Hyderabad-500 085, India.
authors.forename: Nageswara Rao
authors.initials: NR
authors.lastname: Pilli
authors.forename: Jaswanth Kumar
authors.initials: JK
authors.lastname: Inamadugu
authors.forename: Neeraja
authors.initials: N
authors.lastname: Kondreddy
authors.forename: Vijaya Kumari
authors.initials: VK
authors.lastname: Karra
authors.forename: Rajasekhar
authors.initials: R
authors.lastname: Damaramadugu
authors.forename: J V L N Seshagiri
authors.initials: JV
authors.lastname: Rao
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D000077265:Donepezil; D004355:Drug Stability; D006801:Humans; D007189:Indans / Q000097:blood* / Q000493:pharmacokinetics; D008297:Male; D010880:Piperidines / Q000097:blood* / Q000493:pharmacokinetics; D012044:Regression Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: C534900:6-O-desmethyl donepezil; D007189:Indans; D010880:Piperidines; D000077265:Donepezil