Tough adhesives for diverse wet surfaces

Science 2017, vol 357, p378-381

by Dr. Mooney from the John Paulson School of Engineering and Applied Sciences at Harvard University

Funded by NIH

Abstract: Adhesion to wet and dynamic surfaces, including biological tissues, is important in many fields but has proven to be extremely challenging. Existing adhesives are cytotoxic, adhere weakly to tissues, or cannot be used in wet environments. We report a bioinspired design for adhesives consisting of two layers: an adhesive surface and a dissipative matrix.The former adheres to the substrate by electrostatic interactions, covalent bonds, and physical interpenetration. The latter amplifies energy dissipation through hysteresis. The two layers synergistically lead to higher adhesion energies on wet surfaces as compared with those of existing adhesives. Adhesion occurs within minutes, independent of blood exposure and compatible with in vivo dynamic movements. This family of adhesives may be useful in many areas of application, including tissue adhesives, wound dressings, and tissue repair.

My takeaways:

* This seems like a great adaptation of adhesives nature was able to optimize over time. They took the structure of the material snails use for adhesion, simplified it, and optimized the formulation for other applications. They demonstrate a few obvious applications in adhering plastic material to blood soaked tissue. If you have access, I would suggest watching the videos they created in the supporting information for this paper. They show strong adhesion to a live pig heart soaked in blood. They also indicate that their tough adhesive is 8 times stronger at adhesion than current products on the market.

* Naturally, the authors have patented this technology. If I were them, I would focus on bringing a consumer product to market first, then target the medical applications such as large external wounds that need rapid sealing, internal wounds, or other applications like nerve adhesives. My expectation would be that revenue in conjunction with federal funding through SBIRs and DoD grants could mostly fund the development of these class 2 or 3 devices. This biggest hurdle that I would anticipate would be establishing a scalable and reproducible manufacturing process.