Association of mucoadhesive polymeric matrices and liposomes for local delivery of miconazole: A new approach for the treatment of oral candidiasis

Since the local treatment of oral candidiasis usually requires long-term administration of the antifungal drug, an ideal dosage form should be able to maintain the drug release over an extended period, assuring an adequate concentration at the infection site. In this context, we have considered the possibility of a buccal delivery of miconazole nitrate (MN) by mucoadhesive polymeric matrices. The loading of the antifungal drug in a hydrophilic matrix was made possible by taking advantage of the amphiphilic nature of liposomes (LP). The MN-loaded LP were prepared by a thin film evaporation method followed by extrusion, while solid matrices were obtained by freeze-drying a suspension of the LP in a polymeric solution based on chitosan (CH), sodium hyaluronate (HYA), or hydroxypropyl methylcellulose (HPMC). MN-loaded LP measured 284.7 +/- 20.1 nm with homogeneous size distribution, adequate drug encapsulation efficiency (86.0 +/- 3.3 %) and positive zeta potential (+47.4 +/- 3.3). CH and HYA-based formulations almost completely inhibited C. albicans growth after 24 h, even if the HYA-based one released a higher amount of the drug. The CH-based matrix also provided the best mucoadhesive capacity and therefore represents the most promising candidate for the local treatment of oral candidiasis.