title: Fesoterodine stress degradation behavior by liquid chromatography coupled to ultraviolet detection and electrospray ionization mass spectrometry.
abstract: In the present study, a rapid validated stability-indicating LC method was established and comprehensive stress testing of fesoterodine was carried out according to ICH guidelines. Fesoterodine was subjected to stress conditions of acid and basic hydrolysis, oxidation, photolysis and thermal decomposition. The degradation products formed under stress conditions were investigated by LC-UV and LC-ESI-MS. Successful separation of the drug from its degradation products was achieved on a monolithic C(18) column (100 mm × 4.6mm i.d.) maintained at 45°C using acetonitrile-methanol-0.03 mol L(-1) ammonium acetate (pH 3.8) (30:15:55, v/v/v) as the mobile phase. The flow rate was 2.4 mL min(-1) and the detection wavelength was 208 nm. Validation parameters such as specificity, linearity, precision, accuracy, and robustness were evaluated. Chromatographic separation was obtained within 2.5 min and it was suitable for high-throughput analysis. Fragmentation patterns of degradation products formed under different stress conditions were studied and characterized through LC-ESI-MS fragmentation. Based on the results, a drug degradation pathway was proposed, and the validated LC method was successfully applied to the quantitative analysis of fesoterodine in tablet dosage forms, helping to improve quality control and to assure therapeutic efficacy.
authors.affiliation: Laboratory of Research in Pharmaceutical Quality Control, Faculty of Pharmacy, Federal University of Rio Grande do Sul, 90610-000 Porto Alegre-RS, Brazil. maxsilvasangoi@yahoo.com.br
authors.forename: Maximiliano S
authors.initials: MS
authors.lastname: Sangoi
authors.forename: Vítor
authors.initials: V
authors.lastname: Todeschini
authors.forename: Martin
authors.initials: M
authors.lastname: Steppe
mesh_terms: D001559:Benzhydryl Compounds / Q000032:analysis / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D016014:Linear Models; D010084:Oxidation-Reduction; D010782:Photolysis; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D013696:Temperature
chemical_list: D001559:Benzhydryl Compounds; C526675:fesoterodine