Controlled Release of Therapeutics from LbL-Films in Wound Healing Applications
In the past few decades, tremendous focus has been placed on achieving controlled drug release from polymeric matrices with applications ranging from stents to wound dressings. While there has been considerable progress, a number of challenges have yet to be overcome. A promising approach to achieving this drug-incorporation is the layer-by-layer (LbL) technique. Alternating deposition of charged polyelectrolytes can build a stable, multi-drug film under biologically favorable conditions (room temperature and pressure in aqueous solutions). Unfortunately, rampant interdiffusion in these films often results in a highly blended and disoriented structure with degradation profiles considerably different from what was envisioned. Despite one promising report, there is no general strategy for achieving sequential release of multiple drugs, or exerting logical control over the order and rate of their release. Ultimately, we envision controlling the release of multiple drugs over the course of the film’s degradation such that their release can be sequentially distinct with different rates and durations (Figure 1).
To demonstrate the versatility of this platform, we will employ it in wound healing applications. Specific focus will be placed on immediate care of wounds during the first 24 h after being sustained in a battlefield environment. A bandage will be coated with a therapeutic-containing, degradable LbL film for localized delivery, directly to the wound. The release profiles of various therapeutics will be tuned to facilitate wound management.