A Silk Robe for Your Next Implant

This is a cross section of the surface of a silicone breast implant that has been coated with synthetic silk and photographed with an electron microscope. The silk is less than one micrometer thin, so you probably can’t spot it. (Photo courtesy of AMSilk)

You probably know that spider silk is a wonder material because it’s super strong despite being light and stretchy. But silk has another magnificent quality that is now being put to use inside the human body.

Because it is made of proteins that the immune system isn’t inclined to fight, spider silk could make an ideal protective coating for medical implants that otherwise can cause irritation and even rejection in extreme cases. In an experiment underway in Europe, women are receiving silicone breast implants that have been coated with a minuscule layer of artificial silk made by AMSilk, a German company that uses genetically engineered e. coli bacteria to churn out silk proteins. The silk coating eventually wears away and harmlessly degrades, but it’s there long enough for the body to adjust to the implant by forming a capsule of tissue around it, says Lin Römer, AMSilk’s chief science officer.

If these coated implants perform as expected, AMSilk hopes to use the technology on other medical devices, such as pacemakers, and then on electronic implants yet to come. In other words, a material that is millions of years old could smooth the way for body computers of the future. “Our body does not know silicon. Our body does not know polypropylene,” Römer says. “Our body does know proteins.”

Go Deeper