title: Thermal degradation of clozapine-N-oxide to clozapine during gas chromatographic analysis.
abstract: Studies were undertaken to determine if clozapine-N-oxide, the principal urinary metabolite of the antipsychotic agent clozapine, may interfere with the gas chromatographic-mass spectrometric bioanalysis of clozapine. Following injection of clozapine-N-oxide onto a (5% phenyl)methylpolysiloxane capillary column operated at 250 degrees C, significant on-column reduction of clozapine-N-oxide to the parent drug occurred. Accordingly, preparation of biological samples for clozapine determination by gas chromatography should avoid conditions which reportedly co-extract the N-oxide to assure no artifactual contribution of this metabolite in the detection of clozapine.
authors.affiliation: Department of Pharmacy Practice and Hospital Administration, Medical University of South Carolina, Charleston 29425-0810, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Markowitz
authors.forename: K S
authors.initials: KS
authors.lastname: Patrick
mesh_terms: D003024:Clozapine / Q000031:analogs & derivatives* / Q000032:analysis / Q000652:urine; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006358:Hot Temperature; D006801:Humans
chemical_list: D003024:Clozapine; C079149:clozapine N-oxide