Formulation and in vivo anti-inflammatory properties of diclofenac multiple emulsions prepared using Vitellaria paradoxa fat (Shea Butter)

Abstract

Background: In the present study, diclofenac multiple emulsion was formulated using shea butter (Vitellaria paradoxa) as the oil phase and the anti-inflammatory properties of the multiple emulsion assessed in Wistar rats. Methods: The multiple emulsions were prepared using the double emulsification technique and the properties (mean globule size, viscosity and creaming index) of the emulsions were assessed. The in-vivo anti-inflammatory activity of the multiple emulsion was assessed after topical application using two models of inflammation induction, namely formalin-induced paw lick and egg albumin-induced paw oedema Results: Stable diclofenac multiple emulsion was obtained with shea butter as the oil phase and surfactant mixtures, Tween 80: Span 80 ratio of 1:1 with water content of 20%; and Tween 80: Span 80 ratio of 1:1.5 with water content of 25 %. The ranking of inhibition of inflammation after topical application of the formulation was shea butter emulsion < 2 % diclofenac emulsion < standard diclofenac gel < 1 % diclofenac emulsion < shea butter < < No treatment. This indicates that the formulation of shea butter as multiple emulsion significantly (p < 0.05) increased its anti-inflammatory properties while diclofenac multiple emulsion gave a dose dependent activity. In addition, the serum myeloperoxidase activity was significantly lower in treated animals compared to untreated animals. Conclusion: Stable diclofenac multiple emulsions possessing anti-inflammatory activity was successfully developed using shea butter as carrier.