The skin, as the first line of defense, protects the body from mechanical injuries, chemicals and various xenobiotics. It also acts as a natural barrier to pathogenic bacteria. Any breach in this protective barrier will form a wound, which may be colonized with the skin natural flora or microbies from the environment. It becomes infected when bacterial growth overcomes the host defense response. Wound infection adversely impacts quality of life and also adds to the high burden of treatment costs. Treatment of wounds poses several challenges such as the need for maintenance of a clean and moist wound environment that promotes healing, biofilms, local pain at the wound site, achieving sufficient local antimicrobial levels and co-existing medical conditions for example diabetes, malnutrition or immunocompromised states. Development of local wound infection is one of the most important single causes of delayed healing. The therapeutic efficacy of systemic therapies such as antibiotics is affected by adverse events, insufficient local tissue concentrations, local pH, presence of ischemia or necrotic tissue and antibiotic resistance. Hence, they are not routinely used for chronic wounds. Topical formulations, on the other hand, attain high and sustained antimicrobial levels at the wound site and also have fewer systemic adverse events. However, the moisture in the wound can affect the degree of mucoadhesion, stability and consequently drug delivery from topical preparations.

Newer alternative treatments are being developed to overcome these challenges. These include development of nanofibers and nanoparticles as drug delivery systems for antimicrobial agents. Some of the under development products are hydrogels loaded with antimicrobial nanoparticles, hydrogels, and nanoparticles that use naturally-occurring polymers and nanoparticles. Natural components including aloe, cellulose, natural plant extracts and fish skin collagen have been examined as dressings for chronic and burn wounds. Their advantages are “better drug release, improved adhesion, and superior mechanical properties within the wound” and open up more therapeutic options for wound management.

Smith R, Antibiotics (Basel). 2020 Feb 1;9(2):56.