SAMUEL OHIZEGAMEN AIGBOKHAODE

Background: Self emulsifying drug delivery systems (SEDDS) offer a means of enhancingthebioavailability and therapeutic efficacy of drugs with poor water solubility ; Evaluationaselfemulsifying drug delivery system of diclofenac potassium using Castor oil as the lipid phase. Method: Six batches of SEDDS labelled SD1, SD2, SD3, SD4, SD5, and SD6 were preparedbyincorporating diclofenac potassium in SEDDS bases of Castor oil and Tween 80 at varyingcomponent ratios. The resulting formulations were evaluated for their self-emulsificationperformance upon dilution with water by visual inspection and classified according to standardemulsion grading criteria (Grade A, B, or C). They were evaluated for their self-emulsificationperformance, thermodynamic stability and Absorbance values. Result: The emulsification performance demonstrated significant variability across the batches, with formulation SD1 successfully forming a highly stable Grade A emulsion, indicatingrapidand fine self-microemulsification. Conversely, formulations SD2 and SD3 yielded a satisfactoryGrade B emulsion, whereas formulations SD4, SD5 and SD6 resulted in a milky GradeCemulsion, signifying poor emulsification performance. Formulations SD1 - SD3 showedgoodstability, while SD4 – SD6 showed poor stability. The batches had absorbance values whichranged from 0.583 ± 0.154 to 0.719 ± 0.190 showing considerable drug entrapment. Conclusion: The optimal performance of SD1 demonstrates that diclofenac potassiumcanbeeffectively formulated into a stable SEDDS using castor oil, offering a practical approachforimproved in vitro dissolution and enhanced potential for clinical absorption. Keywords: Diclofenac potassium, SEDDS, Self-emulsifying, Castor oil, Tween 80, Dissolutionenhancement, Bioavailability