Newly Developed Hydrogel Improves Soft Tissue Healing

Engineers advance soft tissue injury treatment using an inorganic component found in bone.

The DN gel and the Hap/DN gel. (Image courtesy of Hokkaido University.)

The DN gel and the Hap/DN gel. (Image courtesy of Hokkaido University.)
If you’ve ever torn a ligament or felt pain in your joints before a storm, good news!

A major advancement has been made in the realm of treating joint as well as soft tissue injuries. Engineering researchers have developed a novel hydrogel that is capable of bonding to defected bones.

Previously, the same team of researchers at Hokkaido University developed a high-performing cartilage-regenerating gel called double-network (DN) gel. The DN gel proved to be tough and high-strength while being resilient to wear and capable of facilitating cartilage regeneration. However, DN was mainly composed of water, hindering its ability to bond to a variety of surfaces.

In order to improve to DN gel, the next development added hydroxyapatite (HAp). HAp is the major inorganic material found in bone, and it was added to the surface of the DN gel. This was done by dipping the DN gel in calcium solution and phosphate solution.

The HAp-coated DN gel was then transplanted into a defective bone in a rabbit. Upon observing the performances of the two gels over a four-week time frame, the researchers discovered that the HAp/DN gel bonded to the bone very strongly.

In contrast, the uncoated DN gel did not bond at all. Using electron microscope analysis, the team could see that the newly formed bone in the defected area had penetrated into the gel surface. The treatment had perfectly fused to the bone.

The DN gel and HAp/DN gel implanted into the bone of a rabbit. (Image courtesy of Hokkaido University.)

The DN gel and HAp/DN gel implanted into the bone of a rabbit. (Image courtesy of Hokkaido University.)

One of the leading authors of the paper published on this development, Jian Ping Gong, stated, “The bonding between HAp/DN gel and bone mimics physiological bonding seen with cartilage, ligament and tendon, causing less stress to the body. We expect that the gel could be used to firmly attach artificial ligament or tendon to bone.”

Treating Soft Tissue Injuries

Because damaged cartilage and ligaments cannot be spontaneously repaired inside the body, we turn to artificial transplants to serve this purpose. The HAp/DN gel has proven to be a desirable treatment option for these types of injuries or defects. In the past, development of these treatments has been difficult due to a lack of viable materials for these purposes.

For a different approach to treating soft tissue injuries, read about creating cartilage patches with 3D bioprinting.