Novel solidified reverse micellar solution-based mucoadhesive nano lipid gels encapsulating miconazole nitrate-loaded nanoparticles for improved treatment of oropharyngeal candidiasis

Objective: To develop and evaluate solidified-reverse-micellar-solution (SRMS)-based oromucosal nano lipid gels for improved localised delivery of miconazole nitrate (MN). Methods: Phospholipon (R) 90G and Softisan (R) 154 (3:7) were used to prepare SRMS by fusion. Solid lipid nanoparticles (SLNs, 0.25-1.0% w/w MN) formulated with the SRMS by high shear homogenisation were employed to prepare mucoadhesive nano lipid gels. Physicochemical characterisation, drug release in simulated salivary fluid (SSF) (pH 6.8) and anti-candidal activity were carried out. Results: The SLNs were spherical nanoparticles, had mean size of 133.8 +/- 6.4 to 393.2 +/- 14.5nm, low polydispersity indices, good encapsulation efficiency (EE) (51.96 +/- 2.33-67.12 +/- 1.65%) and drug loading (DL) (19.05 +/- 2.44-24.93 +/- 1.98%). The nano lipid gels were stable, spreadable, pseudoplastic viscoelastic mucoadhesive systems that exhibited better prolonged release and anti-candidal properties than marketed formulation (Daktarin (R) oral gel) (p<0.05). Conclusion: This study has shown that SRMS-based nano lipid gels could be employed to prolong localised oromucosal delivery of MN.