Size-tunable and biodegradable thrombin-functionalized carboxymethyl chitin microspheres for endovascular embolization

As a minimally invasive method, endovascular embolization has been an effective strategy for controlling bleeding and tumor treatment. Herein, carboxymethyl chitin embolic microspheres were prepared with the aqueous two-phase carboxymethyl chitin/polyethylene glycol system without using any crosslinking agents and thrombin-functionalized embolic microsphere named as Thr@CMCHm-30 was made after covalent introduction of thrombin. The size of the microspheres can be adjusted from 5 to 500 mu m. The data of in vitro and in vivo tests indicated that these microspheres possessed good degradability and biocompatibility. Meanwhile, Thr@CMCHm30 can significantly promote blood clotting and enhance the strength of the blood clots. More importantly, Thr@CMCHm-30 displayed better embolization effect than that of the commercial available Gelfoam Alicon (R) and polyvinyl alcohol-based embolic microspheres CalliSpheres (R) in rat femoral vein and rabbit ear artery embolization models. Therefore the size-tunable and biodegradable thrombin-functionalized carboxymethyl chitin microspheres Thr@CMCHm-30 possess great potential for effective hemostasis and endovascular embolization.

Automated summary

This study introduces a novel size-tunable and biodegradable thrombin-functionalized carboxymethyl chitin microspheres, and demonstrates its effectiveness in hemostasis and endovascular embolization through in vitro and in vivo experiments.