Physicochemical and release studies of new mucoadhesive fluconazole delivery systems

Abstract

In this paper, we present results on the sorption and wettability of tablets containing mucoadhesive (Carbopol 974P NF, HEC) and film-forming (Kollidon VA 64) polymers, with fluconazole as a model active pharmaceutical ingredient (API), important from the point of view of designing new mucoadhesive drug delivery systems for potential use for development of mucoadhesive vaginal or buccal dosage forms. Preliminary studies of the powdered polymer mixture with API and the tablets containing the same components in simulated saliva and vaginal fluids were conducted. Wetting properties of the tablets were determined by contact angle measurements using the sessile drop method. On the basis of the measured contact angles, the surface free energy (SFE) was determined according to the Owens-Wendt-Rabel-Käelble (OWRK) approach. The sorption properties of the powders were evaluated by the liquid penetration method. Moreover, in vitro fluconazole release studies were performed using USP 4 apparatus. The composition of the formulation as well as pH of the model fluids were found to significantly influence the surface properties of the tested systems, but simultaneously, composition revealed a weak effect of the above parameters on the rate of drug release from the polymer matrix was observed. It was found that the fluconazole release kinetics for most of the tested tablets can be described by the anomalous or super case II transport mechanism.