6. Formulation of Emulsion Containing Chloramphenicol and Cinnamon Essential Oil for Topical Use

Methicillin-resistance staphylococcus aureus (MRSA) is a fatal pathogen that causes infections in various parts of the body due to high resistance toward wide antibiotics alternatives. The return of chloramphenicol is believed to overcome antibiotic-resistance issues of MRSA. In this study, chloramphenicol was cooperated with cinnamon essential oil in which the combination has been reported to be synergistically effective against MRSA. The emulsion carrier was formulated using both a high-shear homogenizer and an overhead stirrer homogenizer. Three emulsions were prepared at different compositions of cinnamon essential oil, water and surfactant based on the constructed ternary phase diagram. Samples with different formulation (F₁, F₂ and F₃) were subjected to several tests including the stability, rheological, colony and invitro release analysis. F₁, F₂ and F₃ possessed good stability against phase separation for 1 month storage at temperature 4 and 25 °C. All the formulations were having pH values within the range of 3–5 as well as showing no mold and microbial growth after been incubated on nutrient agar plates at controlled conditions. From the rheological aspect, non-Newtonian and pseudoplastic flow behavior well-suited an emulsion for the topical used. A Franz diffusion cell was used in the permeation study where F₁ resulted in up to 60.83% of chloramphenicol permeation through the cellulose acetate membrane. This corresponded to controlled release mechanism and best-fitted to zero-order kinetic behavior (R² = 0.9937). Preliminary studies have proven that the formulated emulsion has a promising potential as topical medicament and could open up new possibilities for the production of pharmaceutical products. The increase in demand of topical skin treatment is predicted in this country together with other neighboring countries. The closely sharing genetic pool and environmental climate result in skyrocketing skin problems. Thus, the formulation could generate a great potential for a better future.