4D printable semi-interpenetrating networks with robust tissue adhesion for smart self-deployable vascular closure

Abstract

Interventional therapy has emerged as a transformative alternative to open surgery owing to its minimal invasiveness and fast recovery. However, it still presents risks of iatrogenic injury from vascular access, necessitating prompt and reliable vascular closure. Although various closure systems have been developed, they often suffer from complicated deployment procedures, potential for loosening, and risk of device migration. Herein, we develop a smart self-deployable vascular closure device enabled by a semi-interpenetrating network (sIPN) that synergistically integrates a programmable shape memory effect and robust tissue adhesion. The sIPN was designed by interpenetrating flexible, dopamine-functionalized poly(tetrahydrofuran) (PTD) chains into a photo-cross-linkable poly(ε-caprolactone)-based copolymer (PCC) network. The vascular closure model was fabricated via a UV-assisted fused deposition modeling printing strategy, significantly reducing mechanical anisotropy while facilitating structural customization. The resulting device exhibits autonomous self-deployment at 37 °C, along with reliable tissue adhesion under physiological conditions (maximum shear strength of 150.5 kPa). In vitro, the material demonstrates exceptional hemocompatibility (below 3%) and excellently enhanced cell migration (up to 38.9%). In vivo, immunofluorescence analysis reveals a promotion for CD31 (162.18%) and aSMA (154.93%) compared to the control group. These results highlight the PTD/PCC sIPN as a bioadaptive, multifunctional material platform for intelligent vascular closure, offering great promise for clinical translation in interventional therapies.