Chapter 3. Controlled Release of Antimicrobial Small Molecules

Controlled release of antimicrobial small molecules is designed to be used for prevention and/or treatment infections associated with a large variety of wound occurrences, ranging from traumatic skin tears and burns to chronic ulcers and complications following surgery and device implantations. The main goal in treating infections is to decrease the bacterial load in the wound site to a level that enables wound healing processes to take place. Local delivery of antibiotics by either topical administration or a delivery device should enable the maintenance of a high local antibiotic concentration for an extended duration of release without exceeding systemic toxicity. The antimicrobial delivery system should be made of biocompatible and biodegradable materials, able to carry a sufficient drug concentration, and release the drug at the appropriate rate for an optimal treatment of the infected tissue. In recent years, various platforms have been developed in order to carry different types of antimicrobial small molecules and treat numerous organs and infections. This chapter describes the main types of these systems. These are based on nanoparticles, fibers, dendrimers, liposomes, nanotubes, and films. Emphasis is placed on processing techniques, nanostructure/microstructure, drug release profiles, biocompatibility and other relevant aspects necessary for advancing the therapeutic field of antimicrobial delivery devices. The final part of this chapter is dedicated to novel concepts in antibiotic-loaded bioresorbable films that we have developed. It focuses on structuring effects of dense and porous films, as well as novel soy protein based systems.