Formulation and In Vitro Evaluation of Mucoadhesive Nystatin Vaginal Gel

Abstract

Nystatin was prepared as vaginal gels using mucoadhesive polymers to provide mucoadhesive property which in turns increase its effectiveness; different formulas were prepared which were evaluated for the in vitro drug release and for their physical properties (swelling index, viscosity, rheological behavior, pH, spreadability, and mucoadhesive characteristics). The influence of type and concentration of gelling agent [2.5 and 3.5 %w/w carboxymethylcellulose (CMC), 0.5 and 1% w/w carbopol 934 (CP 934), and 3 and 4% w/w xanthan gum], besides the effect of addition of different concentration (1, 3, 5, and 10%w/w) of tween 80 (TW.80) as a surfactant on nystatin release from the prepared gels were investigated. All the prepared formulas were observed to have accepted physical properties and with higher release amount after 5 hours in comparison with Nystatin® vaginal cream (Lifepharma, Italy).
It was found that CMC containing gel produced the highest nystatin release compared with other polymer types used, also as the polymer concentration increased, the amount of nystatin released decreased. Addition of 1%w/w TW. 80 increased nystatin release, also the release from CMC containing gel was appeared to increase with increasing TW. 80 concentration (from 1 to 10% w/w), It was found that the formula containing CMC in a concentration of 2.5% w/w and TW. 80 in a concentration of 5% w/w was the formula of choice due to its optimum drug release and physical properties, rheological study revealed that this formula exhibited pseudoplastic flow with shearthinnig behavior and thixotrpy. All formulas were found to follow zero order release kinetics