(313f) Antimicrobial Delivery From Degradable Polymer Coatings

The systemic overuse of broad-spectrum antibiotics has lead to a worldwide rise in antibiotic resistant bacteria. An alternative that could alleviate systemic drug toxicity while maintaining effective local drug concentrations is needed. As a solution to this problem, we have examined the local delivery of antibiotics from degradable coatings. These coatings were formulated using the layer-by-layer assembly technique for the design of drug releasing hydrolytically degradable polyelectrolyte multilayer films. The incorporation and release of a potent glycopeptide antibiotic, vancomycin hydrochloride, from these films was thoroughly examined. Vancomycin hydrochloride is often used as the first line of defense against many resistant gram-positive bacteria strains. Taking advantage of secondary interactions present between film components and varying film assembly technique (dip and spray assembly), coatings were engineered to release drug with varying release profiles over 4 hours to 2.5 days with loadings of 21 to 40 µg/cm². These loadings are highly therapeutic, far exceeding the minimum inhibitory concentration of vancomycin hydrochloride against Staphylococcus aureus. The coatings were applied to bandage materials and found to completely inhibit Staphylococcus aureus growth in vitro. In this work, we have demonstrated the ability to control antibiotic release profiles and drug loading. This control is necessary to address the requirements of varying medical conditions, including those where immediate infection elimination is needed and/or long term infection prevention is required.