title: Development and validation of a stability-indicating capillary zone electrophoretic method for the assessment of entecavir and its correlation with liquid chromatographic methods.
abstract: A stability-indicating capillary zone electrophoresis (CZE) method was validated for the analysis of entecavir in pharmaceutical formulations, using nimesulide as an internal standard. A fused-silica capillary (50 µm i.d.; effective length, 40 cm) was used while being maintained at 25°C; the applied voltage was 25 kV. A background electrolyte solution consisted of a 20 mM sodium tetraborate solution at pH 10. Injections were performed using a pressure mode at 50 mbar for 5 s, with detection at 216 nm. The specificity and stability-indicating capability were proven through forced degradation studies, evaluating also the in vitro cytotoxicity test of the degraded products. The method was linear over the concentration range of 1-200 µg mL(-1) (r(2) = 0.9999), and was applied for the analysis of entecavir in tablet dosage forms. The results were correlated to those of validated conventional and fast LC methods, showing non-significant differences (p > 0.05).
authors.affiliation: Department of Industrial Pharmacy, Federal University of Santa Maria, Santa Maria-RS, Brazil. sdalmora@terra.com.br
authors.forename: Sergio Luiz
authors.initials: SL
authors.lastname: Dalmora
authors.forename: Daniele Rubert
authors.initials: DR
authors.lastname: Nogueira
authors.forename: Felipe Bianchini
authors.initials: FB
authors.lastname: D'Avila
authors.forename: Ricardo Bizogne
authors.initials: RB
authors.lastname: Souto
authors.forename: Diogo Paim
authors.initials: DP
authors.lastname: Leal
mesh_terms: D000818:Animals; D002460:Cell Line; D002853:Chromatography, Liquid / Q000379:methods*; D004304:Dosage Forms; D004355:Drug Stability; D019075:Electrophoresis, Capillary / Q000379:methods*; D006147:Guanine / Q000031:analogs & derivatives* / Q000032:analysis / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D057230:Limit of Detection; D051379:Mice; D012015:Reference Standards; D012680:Sensitivity and Specificity; D013607:Tablets / Q000032:analysis*
chemical_list: D004304:Dosage Forms; D013607:Tablets; C413685:entecavir; D006147:Guanine