Janus Tough Adhesive (JTA): A High-Adhesion, High-Drug-Loading Hydrogel for Enhanced Tendon Healing

As is known to all, tendon injuries are a common condition. After the injury, the function of the tendon cannot be fully restored and is often accompanied by complications such as tissue inflammation and degeneration. Although therapies such as surgery, rehabilitation, transplantation, and medication have been used to treat tendon injuries, treatment deficiencies like failed tendon healing and persistent pain still remain.

Hydrogels that provide mechanical support and sustained drug release therapy have been used to treat tendon injuries. However, most hydrogels have limitations such as poor toughness and the need for cell infiltration or suturing to integrate with surrounding tissues. Therefore, it is of great significance to develop tough hydrogels with adhesive surfaces and high drug-loading capacity to enhance tendon healing.

On January 3, 2022, Harvard University andNovartisResearchers from the company published a research paper titled: Enhanced tendon healing by a tough hydrogel with an adhesive side and high drug-loading capacity in the Nature Biomedical Engineering journal, a subsidiary of Nature.

The research team designed a tough adhesive hydrogel called Janus Tough Adhesive (JTA) for the treatment and prevention of tendon injuries. Studies have shown that JTA exhibits enhanced tissue adhesion and promotes sliding properties of the surrounding tissues. Additionally, JTA can also serve as a drug delivery system for localized drug release.

The research team first studied the tendon adhesion strength and tissue sliding characteristics of JTA. After contacting the bovine tendon model, chitosan rapidly diffused to the tendon surface and generated strong adhesion, which increased over time. In the porcine in situ model, JTA adhered firmly to the pig patellar tendon, flexor tendon, and Achilles tendon, and fit well with the tissue surface.

Next, the research team used human cadaver wrists as models to test the tendon gliding ability on the non-adhesive side of the JTA. The JTA demonstrated low friction resistance while gliding over the palmar plate and passing through the transverse carpal ligament. Additionally, the JTA exhibited excellent biocompatibility and the ability to promote tendon healing in in vivo models.

Next, the research team used corticosteroid triamcinolone (CORT) as a drug model to evaluate the drug-loading capacity and sustained drug release ability of JTA. The CORT loading capacity of JTA reached 25,000 times the solubility limit of CORT, with in vitro drug release lasting over 10 days. Using a rat model with patellar tendon injuries, the high drug-loading capacity of JTA extended the drug dissolution and release time.BioValleyBioon.com）