Formulation and Characterization of Kaffir Lime Oil Nanoemulsion

Kaffir lime oil has many health benefits. However, an obstacle to its commercial use is oxidation during storage. Nanoemulsions (particulate colloidal systems) have been shown to be suitable carriers for lipophilic essential oil constituents due to amphipathic compounds that facilitate solubility. The objectives of this study were to formulate thermodynamically stable kaffir lime oil nanoemulsions and to investigate their physicochemical properties. Air-dried leaves of kaffir lime were subjected to steam distillation to obtain essential oil. Preparation of nanoemulsions was done using the spontaneous emulsification method. Tween 80 and propylene glycol were selected as surfactant mix components. The oil phase consisted of Miglyol 812 as a carrier oil for kaffir lime oil while double-distilled water was used in the aqueous phase. The best formula with transmittance above 95% and highest essential oil content was selected. It contained 20% of Tween 80, 10% of propylene glycol, 1.25% Miglyol 812, and 3.75% kaffir lime essential oil. This formula was then characterized and its thermodynamic stability determined. . The results showed that kaffir lime oil nanoemulsions were thermodynamically stable and robustly withstood variations in temperature, centrifugation, and long-term storage. Additionally, the nanoemulsions had low viscosity, which may facilitate its development as a pharmaceutical compound.