title: Assay of the synthetic estrogen fosfestrol in pharmaceutical formulations using capillary electrophoresis.
abstract: This study reports--for the first time--a capillary electrophoretic method for the determination of fosfestrol, a synthetic estrogen used in the treatment of metastatic prostate cancer. The effects of the carrier ion concentration, injected volume and applied voltage were studied and optimized. A 10 mM sodium tetraborate solution was selected as the carrier electrolyte solution, while the sample was injected hydrodynamically by applying a 20 mmHg vacuum for 1 s. The driving voltage was 30 kV and the absorbance of the analyte (peak height) was monitored at 240 nm. Under the above-mentioned conditions, the migration time of fosfestrol was 6.6 min. Linearity was achieved in the analyte range 3-150 mgL(-1) with the detection limit being 1 mgL(-1). The proposed method is adequately precise (s(r)=2.8% at 100 mgL(-1) fosfestrol, n=10) without the use of an internal standard and was applied to the determination of fosfestrol in a pharmaceutical formulation. The results obtained by the proposed method were in good agreement with those derived from the USP reference method.
authors.affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, GR-54006 Thessaloniki, Greece. themelis@chem.auth.gr
authors.forename: Demetrius
authors.initials: D
authors.lastname: G Themelis
authors.forename: Anastasios V
authors.initials: AV
authors.lastname: Trellopoulos
authors.forename: Paraskevas D
authors.initials: PD
authors.lastname: Tzanavaras
authors.forename: Bo
authors.initials: B
authors.lastname: Karlberg
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000032:analysis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D004054:Diethylstilbestrol / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D004345:Drug Industry; D019075:Electrophoresis, Capillary / Q000379:methods*; D004967:Estrogens / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008956:Models, Chemical; D004364:Pharmaceutical Preparations / Q000032:analysis / Q000737:chemistry*; D011471:Prostatic Neoplasms / Q000188:drug therapy; D015203:Reproducibility of Results; D013997:Time Factors
chemical_list: D018931:Antineoplastic Agents, Hormonal; D004967:Estrogens; D004364:Pharmaceutical Preparations; D004054:Diethylstilbestrol; C004955:fosfestrol