Adhesive organic materials commonly used as an alternative to surgical stitching with sutures often suffer from limited biocompatibility and/or sub-optimal adhesive strength. A potential remedy has been developed by researchers from Okayama University, Japan: a class of biocompatible–biodegradable compounds that shows promising adhesion properties when applied to mouse soft tissues.

The scientists exploited the recent discovery that certain nanostructured materials display remarkable Experiments demonstrated the ability of the novel adhesive to glue various types of mouse soft tissue. Image credit: Okayama Universityadhesiveness. For example, introducing a dispersion of silicon oxide nanoparticles between two hydrogels results in rapid adhesion of the hydrogels — an effect now developed further for industrial, non-clinical applications. To achieve the level of biocompatibility required for clinical usage, the team tested nanoparticles of hydroxyapatite (HAp), an inorganic material found in human hard tissues such as bones and teeth. HAp-composites are routinely used for orthopedic and dental implants, as well as in tissue engineering.

The presence of HAp-nanoparticle dispersions was demonstrated to enhance the level of adhesion of synthetic hydrogels. Drying the dispersions resulted in solid HAp ‘plates’ and increased cohesion between the HAp nanoparticles. Applying the plates as the adhesive agent then led to even better inter-hydrogel adhesion.

Tests on different mouse soft tissues showed that muscle, lung, kidney and other tissues could be successfully glued together. Adhesion strength at least twice that obtained with a commercial organic glue was observed for mouse skin tissues.

The advance is not only relevant for developing new procedures for surgical-wound healing, but also for drug-delivery technologies.