Development and Characterization of Azithromycin-Loaded Microemulsions: A Promising Tool for the Treatment of Bacterial Skin Infections

Abstract

In recent years, the treatment of bacterial skin infections has been considered a major healthcare issue due to the growing emergence of antibiotic-resistant strains of Staphylococcus aureus. The incorporation of antibiotics in appropriate nanosystems could represent a promising strategy, able to overcome several drawbacks of the topical treatment of infections, including poor drug retention within the skin. The present work aims to develop microemulsions containing azithromycin (AZT), a broad-spectrum macrolide antibiotic. Firstly, AZT solubility in various oils, surfactants and co-surfactants was assessed to select the main components. Subsequently, microemulsions composed of vitamin E acetate, Labrasol® and Transcutol® P were prepared and characterized for their pH, viscosity, droplet size, zeta potential and ability to release the drug and to promote its retention inside porcine skin. Antimicrobial activity against S. aureus methicillin-resistant strains (MRSA) and the biocompatibility of microemulsions were evaluated. Microemulsions showed an acceptable pH and were characterized by different droplet sizes and viscosities depending on their composition. Interestingly, they provided a prolonged release of AZT and promoted its accumulation inside the skin. Finally, microemulsions retained AZT efficacy on MRSA and were not cytotoxic. Hence, the developed AZT-loaded microemulsions could be considered as useful nanocarriers for the treatment of antibiotic-resistant infections of the skin.

Development and Characterization of New Miconazole-Based Microemulsions for Buccal Delivery by Implementing a Full Factorial Design Modeling

“…The parameter was important in appreciating stability and explaining phenomena implied in droplet stabilization [ 95 ]. Zeta potential was studied in various micro-/nanoemulsified systems [ 96 , 97 ], including microemulsions with antifungal agents [ 28 , 98 ]. It was clarified that stabilization can be influenced not only by electrostatic repulsions but also by steric stabilization, promoted by polysorbate-based surfactants [ 98 ] and dispersion forces [ 59 ].…”

Exploring Microemulsion Systems for the Incorporation of Glucocorticoids into Bacterial Cellulose: A Novel Approach for Anti-Inflammatory Wound Dressings

“…Furthermore, the samples were stored for 24 h at freezing (−20 °C) and room temperature (25 °C) with two replications of this cycle. Subsequently, the samples were checked for phase separation and transparency ( n = 3) [ 52 , 53 ].…”

New Weapons to Fight against Staphylococcus aureus Skin Infections

“…Microemulsions (MEs) are known to improve skin retention due to their interaction with skin lipids [58], which makes them a promising option for local drug delivery. Abruzzo et al produced MEs composed of vitamin E acetate, Labrasol ® , and Transcutol ® P as azithromycin (Azt) carriers [59]. Formulations M1, M2, and M3 loaded with Azt were obtained using different percentages of each compound.…”