Evaporation-based, co-axial lock-and-key fibrous reservoir for long-term prevention of hypertrophic scars

Many diseases and conditions such as hypertrophic scarring require long-term maintenance over the healing cycle to achieve full recovery. However, there is a lack of wound dressings that can sustain over 90 days of therapeutic release. Inspired by the enhancement of wound healing by the nanofibrous morphology and diverse structures of electrospinning, we report an evaporation-based co-axial electrospun fibrous scaffold incorporating polymer brush gatekept nanocarriers for sustained delivery of therapeutics. The release rates of the system were demonstrated to be tunable through polymer graft length, while the system experienced minimal burst release when submerged under aqueous conditions. As a proof-of-concept, we target hypertrophic scarring by loading the system with doxorubicin, which led to inhibition of fibroblast activity without interfering with cell adhesion. Application of our scaffolds on rabbit ear hypertrophic scar models displayed that our scaffolds effectively reduced collagen density and scar-related gene expression in healing tissues, with improved tissue elevation outcomes. We envision that our long-term release scaffolds will be useful in combating long unresolved clinical dilemma such as tendon adhesion and tumor regression.