Cyanoacrylates

Cyanoacrylates are solvent free adhesives that cure rapidly when pressed into a thin film between two surfaces. Their ease availability and use in various formulations made them attractive to manufacturers a wide variety of medical devices. Unfortunately, earlier generations of cyanoacrylates had several limitations, such as poor thermal resistance and peel strength. Subsequent developments in cyanoacrylate technology have greatly expanded the performance of these adhesives.

Tissue adhesives represent a group of natural and artificial compounds that are currently used for a variety of local applications including hemostasis, wound closure, and fistula repair. The most commonly utilized tissue adhesives in GI endoscopy include cyanoacry- lates, fibrin glues, and thrombin. Other adhesives, such as collagen-based sealants and PEG polymers, are beginning to be studied in various surgical disciplines and may one day find a role in endoscopic practice as well.

Cyanoacrylate glues are easily applied to wounds with good cosmetic results. However, they tend to be brittle and can induce local tissue toxicity. A series of cyanoacrylate monomers with a flexible ether linkage and varying side-chain lengths was synthesized and characterized for potential use as tissue adhesives. The effect of side-chain length on synthesis yield, physical and mechanical properties, formaldehyde generation, cytotoxicity in vitro and biocompatibility in vivo were examined.