(69a) Polyelectrolyte Multilayers for Tunable Delivery of Antibiotics

Multilayered polymer thin films were constructed via the layer-by-layer (LbL) deposition technique using a unique water-hydrolyzable polycation, resulting in coatings that are stable in air but erode top-down in a layer-by-layer fashion when exposed to aqueous physiological environment. The multilayered nature of these films allows for the encapsulations and subsequent sequential releases of multiple drugs, with controls over the dosage and release kinetics of each encapsulated agent. We focus on the development of a coating for sequential delivery of pain killers with anti-inflammatories, antibiotics, and growth factors to be applied onto orthopedic implant surfaces. We have incorporated small-molecule antibiotics into these films without the need for any pre-modification, and demonstrated controls over encapsulation dosage and subsequent release rate through a variety of tuning factors. Several classes of antibiotics are under investigation, some with sustained release over one to two weeks, an ideal duration for infection control over biomedical implant surfaces. Aside from antimicrobial coatings, our findings can also be applied towards coating-based delivery of other therapeutic agents, including proteins and nucleic acids, as well as other active ingredients in the non-medical industries.