A Hierarchical Plug-and-Supply Flap (PASF) for Instant Perfusion and Oxygen Delivery in Large Soft Tissue Repair.

Abstract

Timely and spatially sufficient oxygen delivery remains a significant challenge in large-volume soft tissue repair. Here, we present a novel plug-and-supply flap (PASF) system that integrates hierarchical vasculature and in situ endothelialization to achieve instantaneous perfusion within seconds and provide uniform metabolic support. We fabricated hierarchical vascular networks with high structural precision using a hydrogen-bond reorientation technology, while biofunctionalizing the conduit surface to enable rapid endothelial adhesion via a unique galectin-mediated mechanism, without needing prolonged pre-culture. Computational modeling guided vascular geometry optimization by simulating oxygen diffusion and hemodynamic dynamics, thereby improving both metabolic support and perfusion stability. In a rabbit carotid artery anastomosis model, PASF restored immediate perfusion and enhanced oxidative metabolism, thereby promoting angiogenesis and establishing a pro-regenerative niche. Together, these findings demonstrate a generalizable strategy for engineering perfusable scaffolds that actively modulate the post-implantation niche in soft-tissue reconstruction, where early metabolic support is vital.