title: Another use of silica gel and aqueous eluent for HPLC analysis of clozapine and desmethylclozapine.
abstract: A procedure that involves a high-performance liquid chromatographic system with silica-bonded columns and reversed-phase eluents was fitted from a previously described method to measure clozapine and desmethylclozapine plasma levels. Clozapine and its demethylated metabolite were extracted from alkalinized serum by a liquid-liquid extraction, separated in 10 min, then quantitated at 254 nm at a minimum concentration of 20 ng/mL. The standard curves were linear over the range of 50-3000 ng/mL (r > 0.99) both for clozapine and desmethylclozapine and the assay had good sensitivity and recovery. Intra- and interday coefficients of variation for 200 and 800 ng/mL controls were less than 11.5% for clozapine and desmethylclozapine. This simple and efficient assay was used to monitor clozapine and desmethylclozapine levels from some treatment-refractory schizophrenic patients.
authors.affiliation: Laboratoire de Pharmacologie Clinique et Toxicologie, Centre Hospitalier Universitaire G. Montpied, Clermont-Ferrand, France. francois.coudore@u-clermont1.fr
authors.forename: F
authors.initials: F
authors.lastname: Coudoré
authors.forename: A
authors.initials: A
authors.lastname: Nicolay
authors.forename: M
authors.initials: M
authors.lastname: Hoareau
authors.forename: A
authors.initials: A
authors.lastname: Eschalier
mesh_terms: D014150:Antipsychotic Agents / Q000097:blood* / Q000627:therapeutic use; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003024:Clozapine / Q000031:analogs & derivatives* / Q000097:blood* / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D005782:Gels; D006801:Humans; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000097:blood / Q000188:drug therapy; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide
chemical_list: D014150:Antipsychotic Agents; D005782:Gels; C058272:norclozapine; D012822:Silicon Dioxide; D003024:Clozapine