title: The determination of the geometric isomers and related impurities of dothiepin in a pharmaceutical preparation by capillary electrophoresis.
abstract: The application of capillary zone electrophoresis in the assay of the tricyclic antidepressant drug, dothiepin, in tablets is discussed. The method developed for dothiepin which exists as the cis- and trans-isomers and contains two major related impurities, an 11-oxo compound and a propanamine, utilizes inclusion complexation with beta-cyclodextrin. For optimization of the method the structured procedure of factorial design was used; the electrolyte solution was 50 mM disodium hydrogen phosphate with 10 mM beta-cyclodextrin-propan-1-ol(90:10, v/v). Good precision (RSD = 1.06%, n = 6), linearity (y = 26.84x + 2.25), and correlation (r = 0.999, n = 7) was obtained for trans-dothiepin. The reproducibility of tablet extraction was also acceptable (RSD = 0.77%, n = 6); the recovery of the trans-isomer was 98% (w/w) and the level of cis-isomer in tablets of dothiepin (75 mg) was 5.58% (w/w).
authors.affiliation: Pharmaceutical Chemistry, School of Pharmacy, University of Bradford, UK.
authors.forename: B J
authors.initials: BJ
authors.lastname: Clark
authors.forename: P
authors.initials: P
authors.lastname: Barker
authors.forename: T
authors.initials: T
authors.lastname: Large
mesh_terms: D003505:Cyclodextrins; D004308:Dothiepin / Q000032:analysis* / Q000737:chemistry; D004340:Drug Contamination; D004586:Electrophoresis; D013237:Stereoisomerism; D013607:Tablets
chemical_list: D003505:Cyclodextrins; D013607:Tablets; D004308:Dothiepin