Research ArticleBIOMATERIALS

An injectable shear-thinning biomaterial for endovascular embolization

See allHide authors and affiliations

Science Translational Medicine  16 Nov 2016:
Vol. 8, Issue 365, pp. 365ra156
DOI: 10.1126/scitranslmed.aah5533

You are currently viewing the abstract.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Stopping blood in its tracks

Effective treatments for ruptured blood vessels must be rapidly deployed to promote hemostasis. Avery et al. formulated a gelatin and silicate nanoplatelet hydrogel material that occluded blood flow without requiring thrombus formation. When injected into arteries and veins in mice and pigs, the biomaterial occluded blood flow without evidence of fragmentation or displacement for up to 24 days. Occluded vessels showed evidence of connective tissue replacing the biomaterial in the vessel lumen. Shear-thinning biomaterials represent promising alternatives for stable endovascular embolization.

Abstract

Improved endovascular embolization of vascular conditions can generate better patient outcomes and minimize the need for repeat procedures. However, many embolic materials, such as metallic coils or liquid embolic agents, are associated with limitations and complications such as breakthrough bleeding, coil migration, coil compaction, recanalization, adhesion of the catheter to the embolic agent, or toxicity. Here, we engineered a shear-thinning biomaterial (STB), a nanocomposite hydrogel containing gelatin and silicate nanoplatelets, to function as an embolic agent for endovascular embolization procedures. STBs are injectable through clinical catheters and needles and have hemostatic activity comparable to metallic coils, the current gold standard. In addition, STBs withstand physiological pressures without fragmentation or displacement in elastomeric channels in vitro and in explant vessels ex vivo. In vitro experiments also indicated that STB embolization did not rely on intrinsic thrombosis as coils did for occlusion, suggesting that the biomaterial may be suitable for use in patients on anticoagulation therapy or those with coagulopathy. Using computed tomography imaging, the biomaterial was shown to fully occlude murine and porcine vasculature in vivo and remain at the site of injection without fragmentation or nontarget embolization. Given the advantages of rapid delivery, in vivo stability, and independent occlusion that does not rely on intrinsic thrombosis, STBs offer an alternative gel-based embolic agent with translational potential for endovascular embolization.

View Full Text