Miconazole Nitrate-loaded Microparticles For Buccal Use: Immediate Drug Release and Antifungal Effect

Background: Miconazole nitrate has been widely employed in treatment of oral mycoses, however your immediate bio-availability and location in the affected area is critical. Objective: The aim of this study was to prepare and evaluate Eudragit® L100 and Gantrez MS-955 microparticles containing miconazole nitrate for oral delivery. Methods: Microparticles were prepared by spray-drying method to achieve high encapsulation efficiency and increase the drug solubility. The microparticles were formed containing 10% and 20% of drug on polymer Eudragit® L100 (E10 and E20), Gantrez MS-955 (G10 and G20) or their combination (EG10 and EG20). The influence of formulation factors (polymer:drug ratio, type of polymer) on yield percent, encapsulation efficiency, particle size, Fourier-transformed infrared spectroscopy (FTIR), X-ray diffraction, differential scanning calorimetry, in vitro drug release and antifungal activity were investigated. Results: Acceptable yield, micrometer-sized and drug-loading efficiencies higher than 89% were obtained. No change in FTIR assignments was recorded after the microencapsulation procedure. X-ray and differential scanning calorimetry studies revealed amorphous/non-crystalline formulations. Miconazole nitrate-microparticles provided a remarkable increase of dissolution rate of the drug. Miconazole nitrate and G10, G20 and EG20 microparticles fitted to biexponential kinetic model, and E10, E20 and EG10 microparticles, monoexponential kinetic model. The antifungal activity test demonstrated that miconazole nitrate-microparticles possessed the same anti-Candida albicans activity as the pure drug. Conclusion: These results indicate that miconazole nitrate-microparticles are feasible carriers for increased release of miconazole at oral environment.