TY - JOUR TI - Design and fabrication of salicylic acid-based polyanhydride devices for wound healing and tissue regeneration DO - https://doi.org/doi:10.7282/T3319TFJ PY - 2013 AB - Wound healing and tissue regeneration after injury is regulated by inflammatory response degree and duration. Localized, controlled release of anti-inflammatory drugs at the injury site can modulate inflammation, thereby, controlling the wound healing process. This research uses salicylic acid-based poly(anhydride-esters) (SAPAEs) to release salicylic acid (SA), an anti-inflammatory drug, in a controlled manner for wound healing and tissue regeneration applications. In the first studies, SAPAE-containing bone regeneration devices were developed. SAPAEs were melt-cast as guided bone regeneration (GBR) caps onto osteoconductive scaffolds, then in vitro drug release was quantified. In vivo inflammation and bone regeneration capacity were evaluated. The SAPAE caps suppressed inflammation and had no effect on bone formation in a rabbit cranial trephine defect model. Second, SAPAEs were blended with polycaprolactone (PCL) and electrospun to create flexible GBR mats. Electrospun mat structure, mechanical properties, and in vitro drug release were determined. Mats were assessed in vivo for their ability to prevent heterotopic ossification (HO) in a rat femoral defect model. Initial studies indicate that the SAPAE:PCL blends prevent HO, but also inhibit bone regeneration in the defect site. Third, SAPAE:poly(ethylene glycol) (PEG) copolymers at various ratios were developed for fibrous adhesion prevention. These, copolymers behave as viscous liquids at room temperature. Rheological properties, in vitro drug release profiles, cytotoxicity, and anti-inflammatory activity were assessed. Shear viscosities are comparable with FDA-approved fibrous adhesion barriers and have the additional benefit of drug release to modulate the excessive inflammation that causes adhesion formation. Fourthly, SAPAEs exhibit an initial lag period in drug release, which could be unfavorable in applications where immediate SA release is desired. By varying the amounts of small molecules incorporated into an SAPAE matrix with an 11-day lag period, immediate and constant SA release profiles were achieved. Overall, SAPAEs were utilized to create bone scaffolds and wraps to direct bone growth, as injectable adhesion barrier devices, and to control early SA release. All these approaches were focused on controlling the wound healing process with biodegradable SAPAEs. KW - Biomedical Engineering KW - Wounds and injuries--Treatment KW - Salicylic acid KW - Drug delivery systems KW - Guided tissue regeneration--Equipment and supplies LA - eng ER -