title: Validated LC-MS (ESI) assay for the simultaneous determination of amitriptyline and its metabolite nortriptyline in rat plasma: application to a pharmacokinetic comparison.
abstract: A rapid, sensitive and specific method based on high performance liquid chromatography with electrospray ionization mass spectrometry (HPLC-MS/ESI) has been developed for the simultaneous determination of amitriptyline and nortriptyline in rat plasma. Sample preparation involved liquid-liquid extraction with methyl t-butyl ether after alkalified with 0.5 mol/l NaOH. Chromatographic separation was performed on a XB-C4 column (4.6 mm x 250 mm, 5 microm, Welch Materials) with a mobile phase consisting of 10mM ammonium acetate (0.6 per thousand formic acid)-acetonitrile (60:40, v/v) at a flow rate of 1.0 ml/min. Calibration curves were linear within the ranges of 10-3200 ng/ml for amitriptyline and 10-1000 ng/ml for nortriptyline. This method was successfully applied to the pharmacokinetic study in rats after intravenous injection of amitriptyline hydrochloride.
authors.affiliation: Clinical Pharmacy & Pharmacology Institute, Second Xiangya Hospital, Central South University, Middle Renmin Road 139#, Changsha 410011, Hunan, PR China. sybonnie@163.com
authors.forename: Yuan
authors.initials: Y
authors.lastname: Shen
authors.forename: Rong-Hua
authors.initials: RH
authors.lastname: Zhu
authors.forename: Huan-De
authors.initials: HD
authors.lastname: Li
authors.forename: Yan-Wen
authors.initials: YW
authors.lastname: Liu
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
mesh_terms: D000639:Amitriptyline / Q000097:blood* / Q000493:pharmacokinetics; D000818:Animals; D000929:Antidepressive Agents, Tricyclic / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008297:Male; D009661:Nortriptyline / Q000097:blood* / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D000929:Antidepressive Agents, Tricyclic; D000639:Amitriptyline; D009661:Nortriptyline