Improving the Stability and the Pharmaceutical Properties of Norfloxacin Form C Through Binary Complexes with β-Cyclodextrin
Norfloxacin, an antibiotic that exists in different solid forms, has very unfavorable properties in terms of solubility and stability. Binary complexes of norfloxacin, in the solid form C, and β-cyclodextrin were procured by the kneading method and physical mixture. Their effect on the solubility, the dissolution rate, and the chemical and physical stability of norfloxacin was evaluated. To perform stability studies, the solid samples were stored under accelerated storage conditions, for a period of 6 months. Physical stability was monitored through powder X-ray diffraction, high-resolution 13C solid-state nuclear magnetic resonance, and scanning electron microscopy. The results showed evidence that the kneaded complex increased and modulated the dissolution rate of norfloxacin C. Furthermore, it was demonstrated that the photochemical stability was increased in the complex, without affecting its physical stability. The results point to the conclusion that the new kneading complex of norfloxacin constitutes an alternative tool to formulate a potential oral drug delivery system with improve oral bioavailability.
KEY WORDSnorfloxacin C β-cyclodextrin dissolution chemical stability physical stability
The authors wish to acknowledge the assistance of the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and the Universidad Nacional de Córdoba, both of which provided support and facilities for this investigation. Also, the research group thanks the Secretaría de Ciencia y Técnica de la Universidad Nacional de Córdoba (SECyT-UNC) and Fondo para la Investigación Científica y Tecnológica (FONCYT) for financial support.
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