Tough hydrogel-based tissue adhesives
Existing adhesives are currently insufficient to bind to biological tissues, because they cannot bind strongly to wet or dynamic surfaces. David Mooney’s lab has used a bio-inspired design to create a new tough adhesive (TA) that consists of two layers: an adhesive surface and a dissipative matrix. These layers synergistically lead to adhesion energies on wet surfaces higher than commercially available adhesives. The TA adhered strongly to porcine skin, cartilage, heart, artery, and liver. Adhesion was strong even when the skin was covered in blood, a case in which other products quickly lose adhesive strength. The TA also adhered strongly to a beating porcine heart, as well as to the livers of rats. When implanted in rats, the TA showed lower inflammation than commercially available adhesives.
The ability of the TA to bind wet surfaces and to stay attached upon stretching and during in vivo dynamic organ movements demonstrates its promise for use in a variety of adhesive applications. These include uses as adhesive bandages or skin wound dressings, as well as uses in tissue repair. The strength of the TA could aid in attaching biomedical devices to patients. It may have further applications in drug delivery, where it could be used as a preformed patch or as an injectable solution. The TAs ability to adhere rapidly, but not immediately, would contribute to its ease of clinical use.