Scientists take step closer towards creating artificial cartilages
Washington: Researchers have found a way to create artificial replacement tissue that mimics both the strength and suppleness of native cartilage.
Articular cartilage is the tissue on the ends of bones where they meet at joints in the body - including in the knees, shoulders and hips. It can erode over time or be damaged by injury or overuse, causing pain and lack of mobility.
In 2007 Farshid Guilak, a professor of orthopaedic surgery and biomedical engineering and his team developed a three-dimensional fabric "scaffold" into which stem cells could be injected and successfully "grown" into articular cartilage tissue.
Constructed of minuscule woven fibers, each of the scaffold's seven layers is about as thick as a human hair. The finished product is about 1 millimeter thick.
Since then, the challenge has been to develop the right medium to fill the empty spaces of the scaffold - one that can sustain compressive loads, provide a lubricating surface and potentially support the growth of stem cells on the scaffold.
Xuanhe Zhao, assistant professor of mechanical engineering and materials science, proposed a theory for the design of durable hydrogels (water-based polymer gels) and in 2012 collaborated with a team from Harvard University to develop an exceptionally strong yet pliable interpenetrating-network hydrogel.
"It's extremely tough, flexible and formable, yet highly lubricating," Zhao said. "It has all the mechanical properties of native cartilage and can withstand wear and tear without fracturing."
The study is published in the journal Advanced Functional Materials.