Evaluation of diclofenac sodium incorporation in alginate membranes as potential drug release system

Abstract

In this study, we proposed the use of the biopolymer alginate to produce membranes with diclofenac sodium incorporated as model-drug aiming at wound dressing application with drug delivery. The membranes were prepared by casting and the drug was incorporated directly into alginate solution, being retained within the membrane. Morphological, chemical, mechanical and barrier properties were evaluated, as well as the release kinetics in vitro using simulated exudate fluid at 37 °C. Results show that the membranes are malleable in the glycerol presence and more resistant to water after crosslinking. The incorporation of diclofenac sodium did not affect barrier properties, but influenced the mechanical properties, increasing the total thickness (from 0.108 to 0.209 mm) and reducing tensile strength (from 40.85 to 21.76 MPa). Drug release evaluation shows that anomalous transport is the major rate-controlling mechanism, where the swelling or erosion of the alginate matrix is the major responsible for the diclofenac sodium release, with a small contribution of Fickian diffusion mechanism. The results show the potential of application of the alginate membranes for wound dressings with drug delivery for enhancing healing process.