Stability Testing of Beclomethasone Dipropionate Nanoemulsion

Purpose: To perform stability studies on a nanoemulsion formulation containing beclomethasone dipropionate (BD) and prepared by spontaneous emulsification method.
Method: A nanoemulsion (o/w) containing BD was prepared using eucalyptus oil, Tween-40, ethanol and distilled water. The nanoemulsions were characterized by droplet size, pH, viscosity, conductivity and refractive index. Stability studies were performed according to International Council on Harmonization (ICH) guidelines over a period of 3 months. Droplet size, pH, viscosity, conductivity and refractive index were determined monthly for 3 months. The shelf-life of the nanoemulsion formulation was determined by accelerated stability testing.
Results: The droplet size, conductivity, viscosity, pH and refractive index of the optimized formulations did not change significantly (p ≥ 0.05) after 3 months of storage at room temperature (25 °C). The shelf life was 1.83 years at room temperature.
Conclusion: The study demonstrates that the physical and chemical stability of BD is enhanced when it is formulated as a nanoemulsion.

Keywords
Nanoemulsion; Beclomethasone dipropionate; Shelf-life; Accelerated stability; Viscosity; Conductivity; Refractive index