In Situ Forming Supramolecular Nanofiber Hydrogel as a Biodegradable Liquid Embolic Agent for Postembolization Tissue Remodeling

Biodegradable liquid embolic agents are used in interventional radiology. A solution of gelatin modified with hydrogen-bonding moieties can form nanofiber hydrogels in the blood for endovascular embolization. The nanofiber hydrogel system exhibits tissue-adhesive properties to blood vessels, nonadhesive properties to catheter tubes, and biodegradability. This nanofiber hydrogel may serve as a biodegradable liquid embolic agent for interventional radiology applications.

Abstract

Embolic agents have been widely used to treat blood vessel abnormalities in interventional radiology as a minimally invasive procedure. However, only a few biodegradable liquid embolic agents exhibit high embolization performance, biodegradability, and operability. Herein, the design of in situ-forming supramolecular nanofiber (SNF) hydrogels is reported as biodegradable liquid embolic agents with the assistance of Bayesian optimization through an active learning pipeline. Chemically modified gelatin with hydrogen-bonding moieties produces fibrin-inspired nanofiber-based hydrogels with a high blood coagulation capacity. The low viscosity of the SNF hydrogels makes them injectable using a microcatheter, and the hydrogel shows sufficient tissue adhesion to the blood vessel walls and very weak adhesion to the catheter tubes. Moreover, the SNF hydrogels exhibit high blood compatibility, cytocompatibility, cell-adhesive properties, and biodegradability (in vitro and in vivo). Intravascularly delivered SNF hydrogels induce embolization of rat femoral arteries. This biodegradable liquid embolic agent could be a powerful tool for interventional radiology in the treatment of various diseases, including aortic aneurysm stent grafting, gynecological diseases, and liver cancer.