Thrombin-loaded alginate-calcium microspheres: A novel hemostatic embolic material for transcatheter arterial embolization.

Transcatheter arterial embolization (TAE) is the best non-laparotomy choice for solid visceral organs rupture and bleeding nowadays. In our previous study, a new biodegradable macromolecule material thrombin-loaded alginate-calcium microsphere (TACM) was prepared and its characteristics were investigated preliminarily. In this study, we further investigated the biocompatibility of TACMs, as well as physical characteristic, application method and effect of TACMs with thrombus (embolic agent). The in vivo results attested that TACMs were non-irritating and non-genotoxic with desired biocompatibility, although brought about a slight and temporary inflammation. Application research showed that the function of thrombin was inhibited by common contrast agents, and it was impracticable to add contrast agents in TACMs with thrombus for tracing under X-rays in TAE. Then, a novel delivery method was developed. In addition, stress resistance test indicated that the TACMs with thrombus was significantly stronger than single autologous thrombus, the optimized ratio of TACMs to whole blood was 2:3 for forming mixed thrombus. Finally, large animal experiment revealed that the novel embolic agent - TACMs mixed thrombus was effective and safe in treating hemorrhage of solid abdominal viscera by TAE.