title: Gas chromatographic--mass spectrometric determination of amitriptyline and its major metabolites in human serum.
abstract: A gas chromatographic--electron-impact ionization mass spectrometric method has been developed for the determination of amitriptyline (AMT) and its metabolites, nortriptyline (NT), 10-hydroxyamitriptyline (10-OH-AMT) and 10-hydroxynortriptyline (10-OH-NT) in human serum. The lower limit of detection was 2 ng/ml for all compounds except 5 ng/ml for 10-OH-NT. The calibration curves for AMT and 10-OH-AMT were linear up to 100 ng/ml, and up to 200 ng/ml for NT and 10-OH-NT. The accuracy of the assay in terms of coefficient of variation was less than 7%. The extraction efficiency was almost quantitative for all compounds except 60% for 10-OH-NT. Using this method, human serum samples which had been collected after oral administration of a single 50-mg dose of AMT were analyzed. Ratios of the conjugation of each metabolite were estimated, including AMT.
mesh_terms: D000639:Amitriptyline / Q000031:analogs & derivatives / Q000097:blood*; D001711:Biotransformation; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D008297:Male; D009661:Nortriptyline / Q000097:blood
chemical_list: D000639:Amitriptyline; D009661:Nortriptyline; C033738:10-hydroxyamitriptyline