Co‐Electrospinning Extracellular Matrix with Polycaprolactone Enables a Modular Approach to Balance Bioactivity and Mechanics of a Multifunctional Bone Wrap

Decellularized tissue possesses significant regenerative potential, yet fabricating complex extracellular matrix (ECM) scaffolds remains challenging. Blending with synthetic polymers aids ECM fabrication but often relies on digested ECM, and encapsulation within the synthetic matrix can limit cell-ECM interactions. We recently developed a suspension electrospinning platform to facilitate ECM fabrication without digestion or polymer-carriers. Its integration into a co-electrospinning system enables modular design of composite scaffolds, combining ECM's regenerative potential with the advantages of synthetic polymers. This study compares co-electrospinning and blend electrospinning of polycaprolactone and small intestinal submucosa (SIS) for use as a bone wrap to augment membrane durability, sustain infection control, and enhance vascularity in Masquelet's induced membrane technique. Co-spun wraps improve handling properties compared to ECM wraps; solvent welding is used to achieve target suture retention standards without diminishing SIS content. Unlike blended wraps, co-spun wraps support full-thickness cell infiltration within 4 weeks, release gentamicin at bactericidal concentrations for 6 weeks, and demonstrate angiogenic properties. Co-spun wraps achieve full tissue integration and enhanced membrane vascularity in an in vivo subcutaneous rat model for 6 weeks. These findings highlight the functionality of a co-electrospinning modular design and the efficacy of using a co-spun wrap in bone tissue engineering applications.