Repairing Nerves With Crab Shells?

Researchers have crafted a hybrid of natural and synthetic materials that they believe can help repair severed nerves.

In the clothing industry, mixing polyester with a soft and natural material like cotton makes a new material that's remarkably breathable and wrinkle-free. Now, according to a recent study, researchers have crafted a new hybrid fiber that laces material from crab shells into industrial polyester.

"A nerve guide requires very strict conditions. It needs to be biocompatible, stable in solution, resistant to collapse and also pliable, so that surgeons can suture it to the nerve," study author Miqin Zhang, an experts of material science and engineering said in a statement. "This turns out to be very difficult."

But not impossible. Modern medicine uses collagen - a structural protein derived from animal cells - to make tiny tubes and pathways that support the repair of nerves. However, collagen is expensive, and the protein can sometimes trigger an adverse immune response and rejection.

So that's where crab shells come in. A material called chitosan is found in the shells of crustaceans, making it cheap and readily available. Unlike lab-made collagen, it is biocompatible, meaning that it won't trigger an immune response.

According to Zhang's study, chitosan is fused with polycaprolactone,  a strong, flexible, biodegradable polyester commonly used in sutures. Together they make up nanosized fibers similar to that of the connective tissue that naturally surrounds human cells.

Interestingly, despite its aquatic animal origins, chitosan swells in water, making it weak in wet environments - a vulnerability that it chares with collagen. The study details how a fusion with polyester helps chitosan overcome this flaw, but the blend of materials must be perfect.

After perfecting their blend, the researcher successfully tested the chitosan-polyester blend against another biomaterial under study, polylacticcoglycolic acid, and a commercially available collagen guide. The chitosan hybrid outperformed the other materials and was found by-far the most consistent. However, much more testing will need to be done before its ready for the medial field.

The results were detailed in the journal Advanced Materials.