A cyanoacrylate/triethyl citrate/nanosilica-based closure glue with wet-adhesion capability for treatment of superficial varicose veins

Abstract

Varicose veins in legs are common in clinics. Currently, medical adhesive-based, minimally invasive endovenous occlusion is used to treat them. However, the most common cyanoacrylate medical adhesives do not perform well when used under blood/wet conditions. In particular, poor adhesion, short curing time, and high heat release greatly limit their clinical use. In this paper, we demonstrate the use of a composite system composed of butyl-cyanoacrylate, triethyl citrate, and nanosilica that exhibits a blood/wet-adhesion capability to serve as a new sealing glue. Hydrophobic triethyl citrate groups displace boundary waters while also protecting cyanoacrylate monomers from undergoing rapid polymerization. Nanosilica increases viscosity, which contributes to in situ extrusion molding and retention. An optimal formulation, FAL-006, exhibited good physical and chemical properties in vitro. The performed additional safety assays indicated that FAL-006 has good biocompatibility. The closure efficiency of FAL-006 in vivo was evaluated in both a rat abdominal aortic closure model and in a sheep lower limb venous closure model. Taken together, these results indicate that FAL-006 exhibits promising potential for use in clinical applications. Furthermore, this study provides a new strategy for designing underwater adhesive agents for additional clinical applications, and a strategy for constructing other biomaterials needed for use under wet conditions.