Development and swelling of non-aqueous microemulsions containing nanoparticles for exudate control and localized release of propranolol and adenosine for wound care

In this study, we developed non-aqueous microemulsions containing alginate nanoparticles capable of swelling in the presence of fluids with the goal of controlling the excess of wound exudate, provide sustained local release of adenosine and propranolol and aid wound healing. Microemulsions were obtained with phosphatidylcholine (PC), monoolein, sunflower oil and propylene glycol. Alginate nanoparticles (279 nm and -36,2 mV) were obtained by external gelation. Adenosine was incorporated at 1% in the nanoparticles (encapsulation efficiency of 79,44%), while propranolol was incorporated in the microemulsion (1%). Increasing monoolein (to 66%) in the microemulsion led to the hexagonal phase formation in the presence of water (up to 40%), while the increase of PC (to 66%) led to the lamellar phase formation. Nanoparticle incorporation did not alter the swelling behavior of microemulsions. These results suggest the potential applicability of the formulation to control excessive wound exudate and co-deliver drugs to aid healing.