Preformulation and in vitro physicochemical characterization of fenofibrate-loaded emulsion

The objective of this study was to prepare a fenofibrate-loaded emulsion. The emulsion was formulated by mixing olive oil, surfactants (mixture of Tween 20 and Tween 80), and distilled water. To find the emulsion composition, the phase diagram was investigated based on the mixture of olive oil, surfactants, and distilled water. From the phase diagram, one-phase formulations were selected and particle sizes of those formulations were compared. Stability was confirmed for 4 weeks at 4 °C based on the change in particle size. The effect of dilution on the pH of the emulsion formulations was observed. The concentration of olive oil was 5 %, enough to obtain a small-sized emulsion. The surfactants were used as a mixture of Tween 20 and Tween 80 in a 1:2 ratio to show high solubility of fenofibrate. Three formulations, termed E1, E2, and E3, showed relatively small-sized emulsion. The fenofibrate-loaded E2 formulations showed smaller particle sizes than other formulations. The three formulations were physically stable for 4 weeks with no significant change in particle size. Dilution with distilled water did not alter the pH of the three emulsion formulations, but changed the conductivity. In conclusion, fenofibrate was solubilized by the emulsion formulation, the stability of the emulsion formulation was maintained at 4 °C, and the pH of formulation was not altered, but the conductivity of formulation was changed by dilution with distilled water.