title: Stability study of flutamide in solid state and in aqueous solution.
abstract: A high-performance liquid chromatography (HPLC) assay has been developed for the determination of flutamide and its degradation products. Using this method, the influence of important formulation factors on the stability of flutamide has been estimated. The stability studies have been carried out in solid state as well as in aqueous solution. The results obtained have shown a good stability for flutamide in solid state. This drug remained practically unchanged after a four-month assay in adverse temperature and humidity conditions. On the other hand, the results obtained from the stability study in solution during 12 days have shown that flutamide in aqueous solution underwent a clear degradation at mean or high temperature (22 degrees C, 37 degrees C) and acidic pH conditions (1.1). With respect to the influence of ionic strength, it has been found that the presence of sodium chloride prevents the degradation of flutamide in aqueous solution. The second-order kinetics model provides the best fit for highly degraded solutions.
authors.affiliation: Departamento de Farmacia y Tecnología Farmaceútica, Facultad de Farmacia, Universidad de Sevilla, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Miranda
authors.forename: I
authors.initials: I
authors.lastname: Caraballo
authors.forename: M
authors.initials: M
authors.lastname: Millán
mesh_terms: D000704:Analysis of Variance; D000726:Androgen Antagonists / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid; D004355:Drug Stability; D005485:Flutamide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009994:Osmolar Concentration; D019999:Pharmaceutical Solutions / Q000737:chemistry*; D012044:Regression Analysis; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D000726:Androgen Antagonists; D019999:Pharmaceutical Solutions; D014867:Water; D005485:Flutamide