Transdermal delivery of diclofenac using microemulsions

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Dermatology

Background:

• Transdermal drug delivery offers a non-invasive route for systemic medication.
• Microemulsions provide a promising vehicle for enhancing the solubility and skin permeation of poorly soluble drugs like diclofenac diethylammonium (DDA).
• Optimizing microemulsion components is crucial for effective percutaneous absorption.

Purpose of the Study:

• To develop and optimize an oil-in-water (O/W) microemulsion for transdermal delivery of diclofenac diethylammonium (DDA).
• To investigate the influence of formulation components on the skin permeation of DDA.
• To determine the optimal microemulsion composition for enhanced percutaneous absorption.

Main Methods:

• Development of an O/W microemulsion system utilizing lauryl alcohol as the oil phase.
• Construction of pseudoternary phase diagrams to identify microemulsion formation regions.
• Evaluation of DDA skin permeation using excised rat skins and analysis of formulation component effects.

Main Results:

• Lauryl alcohol was selected for its solubilizing capacity and ability to enhance DDA skin permeation.
• The optimal microemulsion formulation comprised 1.16% DDA, 5% lauryl alcohol, 60% water, and 34.54% Labrasol/ethanol (1:2).
• Percutaneous absorption of DDA was positively correlated with increased lauryl alcohol and water content, and decreased Labrasol:ethanol ratio.

Conclusions:

• The developed O/W microemulsion system effectively enhances the transdermal delivery of diclofenac diethylammonium.
• Formulation parameters, including oil, water, surfactant, and cosurfactant concentrations, significantly impact DDA's percutaneous absorption.
• This optimized microemulsion holds potential for improved topical and transdermal therapeutic applications of DDA.