Practical level 'artificial cartilage' with the same performance as the real one will be developed

Researchers at Duke University announced that they have developed a new artificial cartilage made of gel . The new type of artificial cartilage that has been developed has strength and durability comparable to that of real cartilage, and is capable of absorbing 2-3 times the body weight.

A Synthetic Hydrogel Composite with the Mechanical Behavior and Durability of Cartilage-Yang--Advanced Functional Materials-Wiley Online Library
https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202003451

From the Lab, the First Cartilage-Mimicking Gel That's Strong Enough for Knees | Duke Today
https://today.duke.edu/2020/06/lab-first-cartilage-mimicking-gel-strong-enough-knees

It is said that nearly 800,000 artificial knee joint replacement surgeries are performed each year in the United States to replace a knee joint that has been deformed due to osteoarthritis or rheumatoid arthritis with an artificial joint. However, it is said that the current artificial knee joint only lasts about 20 years. Especially for cartilage that absorbs the force applied to the knee, 'a material that is slippery, absorbs impact, and does not harm nearby cells' Research and development is underway.

Meanwhile, a research team led by Professor Benjamin Wiley of Duke University's Department of Chemistry and Professor Ken Gull of Engineering Department focused on gels, which have been viewed as promising materials for artificial cartilage since the 1970s. Gel had the property of being “slippery and absorbing shocks”, but the problem was that its strength was too low to be used on a heavy weight area such as the knee.

Therefore, the research team developed a gel composed of two polymers. This gel has a structure in which a polymer with a string-like structure like elastic spaghetti is intertwined with a polymer with a sturdy and stitch-like structure, and cellulose fibers reinforce the stitches of the polymer. I will. When the gel is pulled, the shape is retained by the cellulose fibers, and when it is crushed, water molecules attach due to the electric charge of the polymer and try to return to the original shape. In addition, about 60% of this gel is made of water.

When the research team investigated this new gel while comparing it with other gels, it was found that it was as strong as real cartilage. In addition, after conducting experiments to pull the new gel 100,000 times, it was confirmed that the strength was comparable to that of porous titanium used for artificial bone. Furthermore, even if a 45 kg weight was placed on the new gel, it did not collapse. 'The strength of the new gel exceeded our initial expectations,' said William Kochute, a graduate student and one of the research teams.

In addition, we conducted an experiment of rubbing the new gel on natural cartilage for 1 million times. understood. Experiments have also shown that it is harmless to human cells.

Although the new gel material is very innovative in terms of performance, it is still at the laboratory level at the time of writing the article, and it will take at least another three years to advance the research to a clinically usable level, Professor Wiley said. I am watching. The research team said it would implant the gel in sheep to confirm safety before entering clinical trials.