Preparation and Characterization of Mucoadhesive Thermoresponsive Systems Containing Propolis for the Treatment of Vulvovaginal Candidiasis

This work describes the preparation and characterization of mucoadhesive thermoresponsive systems consisted of poloxamer 407 (P407), Carbopol® 934P (C934P), and propolis to treat vulvovaginal candidiasis (VVC). Systems were obtained with different percentages of P407 and C934P to deliver propolis, a potent drug against VVC. Temperature of gelation, hardness, compressibility, adhesiveness, elasticity, cohesiveness, mucoadhesion, rheology (continuous flow and oscillatory), in vitro drug release, and antimicrobial activity were evaluated. Increasing the polymer content or temperature and the drug presence significantly increased mechanical properties of formulations. These exhibited pseudoplastic flow and low degrees of thixotropy. In most samples, increasing the C934P content significantly changed the oscillatory rheological properties. Formulations showed thermoresponsive behavior, existing as a liquid at room temperature and gel at 34°C-37°C. Propolis release from formulations was controlled by phenomenon of relaxation of polymer chains or displayed anomalous behavior, dependent of concentration of each polymer. The in vitro antimicrobial activity of preparations was evaluated against microorganisms of vaginal importance (Candida albicans, Candida glabrata, Candida parapsilosis, Candida tropicalis, and Saccharomyces cerevisiae), displaying activity against all yeast tested. The data obtained for these systems indicate a potentially useful role in the treatment of VVC and suggest they are worthy of clinical evaluation.