Sticky Slug Trail-Inspired medical adhesive

Wet skin not a problem with super-strong bio-compatible adhesive.

Wyss Institute at Harvard UniversityA new, flexible adhesive material inspired by the glue secreted by slugs adheres to biological tissues (even when wet) without causing toxicity, and can be formed into either sheets (teal blue) or custom shapes (dark blue).

A super-strong “tough adhesive” inspired by SLUGS has been created that is biocompatible and binds to tissues with the strength of the human body’s own cartilage.

Wet skin is one challenge for medical adhesives. Others are blood, serum, and other fluids that can impair the healing process of various internal injuries.

Bio-adhesive materials have often been toxic, inflexible when dry, or incapable of binding to biological tissue properly.

However, the slug glue-inspired material is both non-toxic and performs the task assigned even when wet. The material can be formed into teal-blue sheets or dark-blue custom shapes at the Wyss Institute for Biologically Inspired Engineering, Harvard.

Dr Jianyu Li, formerly of the Wyss Institute and now Ph.D Assistant Professor at McGill University, was inspired by the Dusky Arion (Arion subfuscus) snail, common in Europe and parts of the United States.

It was found to secrete a type of mucus that makes it difficult for a predator to pry it off a surface to which it had glued itself when threatened.

Li and his team went on to create a double-layered hydrogel of an alginate-polyacrylamide matrix supporting an adhesive layer that had positively-charged polymers protruding from its surface.

Li said: “Most prior material designs have focused only on the interface between the tissue and the adhesive. Our adhesive is able to dissipate energy through its matrix layer, which enables it to deform much more before it breaks.”