• JOSE RAUL MEDINA Departamento Sistemas Biologicos Universidad Autonoma Metropolitana-Xochimilco
  • Araceli Uribe Departamento Sistemas Biologicos Universidad Autonoma Metropolitana-Xochimilco
  • Marcela Hurtado Departamento Sistemas Biologicos Universidad Autonoma Metropolitana-Xochimilco
  • ADRIANA MIRIAM DOMINGUEZ-RAMIREZ Departamento Sistemas Biologicos Universidad Autonoma Metropolitana-Xochimilco


Naproxen sodium, Flow-through cell method, Immediate-release generic products


Objective: To perform an in vitro equivalence study of naproxen sodium from six immediate release oral dosage forms under the hydrodynamic environments generated by the flow-through cell method and the USP paddle apparatus.

Methods: Dissolution method was properly validated according to standard criteria. Dissolution profiles of all formulations were carried out with an automated flow-through cell (laminar flow at 16 ml/min with 22.6 mm cells) and the USP Apparatus 2 (50 rpm). 0.1 M phosphate buffer pH 7.4 at 37.0±0.5 °C was used as the dissolution medium. Spectrophotometric determination of drug at 332 nm was carried out during 45 min. Dissolution profiles were compared with model-dependent and independent approaches.

Results: Significant difference with model-independent parameters, mean dissolution time and dissolution efficiency, using both USP apparatuses, were found (*P<0.05). Best fitting of dissolution data was obtained using the sigmoidal model (R2>0.99). Only with the flow-through cell method linear regression between mean dissolution time and t63.2% values was significant (*P<0.05).

Conclusion: The study reveals significant differences in dissolution rate and a great variability for all naproxen sodium tablets when the USP paddle apparatus is used. The alternative dissolution test with the flow-through cell method allows obtaining reliable data which facilitates in vitro equivalence respect the reference product dissolution behavior.



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How to Cite

MEDINA, J. R., A. Uribe, M. Hurtado, and A. M. DOMINGUEZ-RAMIREZ. “IN VITRO EQUIVALENCE STUDY OF GENERIC NAPROXEN SODIUM TABLETS USING THE USP PADDLE APPARATUS AND THE FLOW-THROUGH CELL METHOD”. International Journal of Pharmacy and Pharmaceutical Sciences, vol. 7, no. 7, July 2015, pp. 348-54,



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