Cartilage plays a vital role in the knee, but unfortunately, once the cartilage is damaged or worn, it is difficult to repair and usually needs to be replaced, according tomedia reports. Now, researchers at Duke University have created a new hydrogel that is strong enough to be as strong as natural cartilage.
The knee is the main force of the body, so the cartilage there must be strong enough to support the weight, but also soft enough to cushion the force of each step. But when these useful things get hurt, or wear out after decades of continuous use, they don’t work very well. Sometimes the only thing you can do is have a full knee replacement, but it’s never as good as it used to be.
The potential of hydrogels as cartilage substitutes has long been studied. This is a versatile material, as the name suggests, a gel consisting mainly of water. They are increasingly used in medical fields such as helping wounds heal, hemorrhaging, and even stimulating tissue regeneration.
Although it is expected to be a substitute for knee cartilage, hydrogels are mostly too fragile to support such a large weight. But now, researchers at Duke University claim to have created a new version of the material that has the mechanical properties of cartilage. The new hydrogel is made up of several polymer chains of mesh woven together. One network consists of elastic strands, while the second is more rigid, with a negative charge. The third network contains cellulose fibers to strengthen the structure.
Together, these three networks give the hydrogel the ability to return to its original shape after being stretched or squeezed. Cellulose fibers are helpful for the first point because they are resistant to being pulled and the material from tearing. At the same time, rigid polymer networks are counterproductive to crowding pressure because negatively charged strands are mutually exclusive.
“Only the combination of these three ingredients is soft and rigid, so it’s strong. Yang Feichen, co-author of the study, said. In tests, the team demonstrated the capability of a new hydrogel. A coin-sized hydrogel disc can withstand a 100-pound (45 kg) kettlebell weight without tearing or losing shape. It was stretched 100,000 times and found to be as strong as the porous titanium currently used in bone implants. That’s even better than the team expected. Finally, it rubs 1 million times with natural cartilage samples and finds it to be four times more wear-resistant than existing synthetic cartilage, just as it is.
The team says the new hydrogel sifes as a promising alternative to knee-damaged cartilage, but it could take years at the earliest. At the same time, the researchers plan to design an implant that can be tested on sheep.
The study was published in the journal Advanced Functional Materials.