Combining strategies to optimize a gel formulation containing miconazole: the influence of modified cyclodextrin on textural properties and drug release

Abstract

Background: Miconazol, an antimycotic drug, is commonly formulated into semisolid formulations designed to be applied in the oral cavity to treat oral candidiasis. However, given its limited aqueous solubility, permeation through the biological membranes is low and therefore its activity is also limited. Cyclodextrins (CDs) have been widely used to increase the solubility and stability of poorly water-soluble drugs. Aim: The aim of this study is to formulate a gel containing an inclusion complex between a modified CD, methyl-β-cyclodextrin (MβCD), and miconazole (MCZ). The influence of the CD on the textural properties of the prepared gel and the drug release from formulation were evaluated. Methods: The gels were prepared using two polymers, Carbopol 71G and Pluronic F127, which were selected taking into account their bioadhesiveness and thermal-sensitive gelling properties, respectively. Texture profile analyses were performed at two different temperatures to ascertain the influence of the temperature on the gel texture properties. The in vitro MCZ release profiles from the prepared gel and the commercial gel formulations were evaluated and compared using modified Franz diffusion cells. Results: The addition of MβCD to the gel resulted in a decrease of the gel adhesiveness and firmness, and the MCZ release profile through f1 and f2 proved to be similar to the commercial product. Conclusions: A gel comprising miconazol in the form of an inclusion complex with MβCD showed suitable textural properties to be applied to the buccal mucosa. The MβCD enhanced the solubility of the MCZ in the gel formulation resulting in adequate in vitro drug release profiles.