The tape developed by MIT researchers acts in seconds, in contrast to the existing adhesives which need minutes to seal tissues together. The challenge was to develop a glue efficiently reacting on wet surfaces. While the previously developed tissue adhesives rely on dissolution of the glue particles in the water between the surfaces in order to bind them together, the novel DST absorbs the water first, and then binds the tissues on the dried site. The water-removing agent used is polyacrylic acid doped with hydroxysuccinimide ester. The role of the compounds is to enhance the drying process and immediately form strong intermolecular bonds with proteins in the tissue.
This mechanism is inspired by a spider's strategy of catching prey in wet conditions. The substance used in nature consists of charged polysaccharides clearing the wet water off the surface, allowing the glue to act immediately on the dried patch.
Depending on the need, the tape’s “living time” in the body can be adjusted by choosing a substance with a certain degradation rate. For example, gelatin can be used if the adhesive is needed for a couple of days, while a polysaccharide chitosan usually lasts months in human body.
The tests were conducted in rats’ hearts, ex vivo porcine lungs, stomachs and hearts. The researchers demonstrated the ability of the tape to adhere to dynamic tissues as beating heart and that it can be used to apply wearable devices onto wet tissues.
The novel adhesive is potentially a game-changer. The risks related to surgical stitches can be reduced and treating damaged soft tissues made easier. However, the research is still in early stages and years will pass before the invention can be implemented in operating rooms.